Story highlights Ukraine recognizes Russian cargo as humanitarian aid, but delay likely in delivery of goods

Ukraine says it destroyed part of Russian military convoy that crossed border

British media outlets report they saw military vehicles cross from Russia into Ukraine

One month after Malaysia Flight 17 was shot down over Ukraine, government military forces there said they've made advances Sunday against pro-Russian separatists.

Ukrainian forces regained control over the strategic town of Yasynuvata in Donetsk in the southeastern part of the country, according to the official Twitter account of President Petro Poroshenko. They've also made gains in Luhansk in the eastern part of Ukraine, government forces told CNN. The Ukrainian army has entered Donetsk and raised the Ukrainian flag in front of the district's police offices, said National Defense and Security Council spokesman Col. Andriy Lysenko.

Yet the site of crash MH17 is still unsafe as fighting near it rages, officials tell CNN.

Most investigators left Kiev this week but small teams from several countries remain in Ukraine on standby. For now, the search is officially suspended.

All 298 people on the Boeing 777 were killed when it crashed near the Russian border in eastern Ukraine. Ukrainian and U.S. officials have alleged that a Russian-made missile system was responsible for shooting the aircraft down. The separatists and Russians deny that.

JUST WATCHED Ukrainian MiG shot down by separatists Replay More Videos ... MUST WATCH Ukrainian MiG shot down by separatists 02:05

Photos: Photos: Crisis in Ukraine Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Pro-Russian rebels fire artillery Tuesday, October 14, at Donetsk Sergey Prokofiev International Airport, which is on the outskirts of Donetsk, Ukraine. Fighting between Ukrainian troops and pro-Russian rebels in the country has left more than 3,000 people dead since mid-April, according to the United Nations. Hide Caption 1 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Smoke rises behind the train station in Donetsk, Ukraine, during an artillery battle between pro-Russian rebels and Ukrainian government forces on Sunday, October 12. Hide Caption 2 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian President Petro Poroshenko, center, inspects Ukrainian army positions close to Donetsk on Friday, October 10. Hide Caption 3 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – The main terminal of Donetsk Sergey Prokofiev International Airport is hit by shelling during fighting between pro-Russian rebels and Ukrainian forces on Wednesday, October 8. Hide Caption 4 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Pro-Russian rebels fire mortars toward Ukrainian positions near to the Donetsk airport on October 8. Hide Caption 5 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel walks past a burning house after shelling in the town of Donetsk, Ukraine, on Sunday, October 5. Hide Caption 6 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – An Ukrainian sniper aims his weapon at a checkpoint near Popasna, Ukraine, on Thursday, October 2. Hide Caption 7 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Smoke rises from the area near the Donetsk airport after heavy shelling on October 2. Hide Caption 8 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – An injured man is transported at a hospital after shelling in Donetsk on Wednesday, October 1. Hide Caption 9 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A woman injured at a bus station cries at a Donetsk hospital on October 1. Hide Caption 10 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel guards a damaged school in Donetsk on October 1. Hide Caption 11 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian servicemen patrol in the Donetsk region on Friday, September 26. Hide Caption 12 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel guards a destroyed bridge in Nyzhnya Krynka, Ukraine, on Tuesday, September 23. Hide Caption 13 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Residents clean up debris at a building damaged by rockets in Debaltseve, Ukraine, on Monday, September 22. Hide Caption 14 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A firefighter checks out a damaged office building after shelling in Donetsk on Sunday, September 21. Hide Caption 15 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A Ukrainian soldier guards pro-Russian rebels during a prisoner exchange near Donetsk on September 21. Hide Caption 16 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Members of the Ukrainian military, held as prisoners of war, sit in a bus waiting to be exchanged near Donetsk on Saturday, September 20. Hide Caption 17 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Smoke rises after an explosion at a weapons factory controlled by pro-Russian rebels near Donetsk on September 20. The cause of the explosion was not immediately known. Hide Caption 18 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A Ukrainian helicopter patrols an area near Donetsk on September 20. Hide Caption 19 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A firefighter walks past the rubble of a building destroyed by shelling in Donetsk on Wednesday, September 17. Hide Caption 20 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A protester holds a smoke bomb during a demonstration outside the Presidential Palace in Kiev, Ukraine, on September 17. Activists protested the adoption of legislation giving greater autonomy to rebel-held parts of eastern Ukraine's Donetsk and Luhansk regions. Hide Caption 21 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A man covers the body of his mother, who was killed on a bus during a battle in Donetsk on Tuesday, September 16. Hide Caption 22 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – People walk through a market Monday, September 15, in the Kievsky district of Donetsk. Hide Caption 23 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Smoke rises around the Donetsk International Airport on Saturday, September 13, as shelling continues between pro-Russian rebels and the Ukrainian army. Hide Caption 24 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A Ukrainian soldier stands guard as residents rally in support of a united Ukraine in the southern Ukrainian city of Mariupol on September 13. Hide Caption 25 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Russian trucks, flying Russian flags and carrying humanitarian aid for eastern Ukraine, line up at a border checkpoint in Donetsk on September 13. Hide Caption 26 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Workers unload supplies from Russia in Luhansk, Ukraine, on September 13. More than 200 Russian trucks entered Ukraine with supplies for the city, which has been cut off from electricity and water for weeks. Hide Caption 27 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian soldiers ride on an armored vehicle near Kramatorsk, Ukraine, on September 13. Hide Caption 28 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – People look at a large crater from a reported missile strike that hit a bus station Friday, September 12, in Makiivka, Ukraine. Hide Caption 29 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Workers clear rubble Thursday, September 11, after the bombing of a mine in Donetsk. Hide Caption 30 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A column of Ukrainian forces is seen in Volnovakha, Ukraine, on September 11. Hide Caption 31 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – An elderly woman sits next to a Ukrainian soldier standing guard in Volnovakha on September 11. Hide Caption 32 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Armed pro-Russian rebels walk September 11 in front of the destroyed Luhansk International Airport. The rebels took control of the airport on September 1 after heavy fighting with the Ukrainian army. Hide Caption 33 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Residents of Lutuhyne, Ukraine, push containers in a wheelbarrow September 11 as they walk between destroyed armored vehicles left behind by the Ukrainian army. Hide Caption 34 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian troops protect themselves from a nearby shooting in Debaltseve on Tuesday, September 9. Hide Caption 35 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Young residents of Berdyansk, Ukraine, dig trenches September 9 to help Ukrainian forces protect the city from possible rebel attacks. Hide Caption 36 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian President Petro Poroshenko, left, inspects military personnel during a visit to Mariupol on Monday, September 8. Hide Caption 37 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel stands next to a truck with a heavy machine gun attached to it Sunday, September 7, in Donetsk. Hide Caption 38 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Homes smolder after being hit by shelling in Donetsk on September 7. Hide Caption 39 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A woman stands next to a road sign September 7 after an overnight bombing attack at an Ukrainian army checkpoint on the outskirts of Mariupol. Hide Caption 40 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian troops stand on a deserted road as they patrol the border area of the Donetsk and Luhansk regions Friday, September 5, near Debaltseve. Hide Caption 41 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A man repairs damage to a building caused by shelling in Donetsk on September 5. Hide Caption 42 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Smoke rises on the outskirts of Mariupol after pro-Russian rebels fired heavy artillery on September 5. Hide Caption 43 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian soldiers ride a tank on a road close to where pro-Russian rebels fired heavy artillery outside Mariupol on September 5. Hide Caption 44 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A wounded Ukrainian soldier is helped by a medical team on the outskirts of Mariupol on September 5. Hide Caption 45 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel holds a destroyed weapon in the village of Novokaterynivka, Ukraine, on Thursday, September 4. Hide Caption 46 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Unmarked military vehicles burn on a country road in Berezove, Ukraine, on September 4 after a clash between Ukrainian troops and pro-Russian rebels. For months, Ukrainian government forces have been fighting the rebels near Ukraine's eastern border with Russia. Hide Caption 47 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – People wait by their cars near Berezove on September 4 as rockets hit the road ahead. Hide Caption 48 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel holds a dog, which has a hand grenade attached to its leash, in Donetsk on Wednesday, September 3. Hide Caption 49 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Pro-Russian rebels fire at Ukrainian army positions in Donetsk on September 3. Hide Caption 50 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A Ukrainian military vehicle patrols in the Donetsk region on September 3. Hide Caption 51 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Pro-Russian rebels hold a man near a column of destroyed Ukrainian military vehicles in Novokaterynivka on Tuesday, September 2. Hide Caption 52 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A Ukrainian military truck passes by a serviceman resting in his military camp in Ukraine's Donetsk region on September 2. Hide Caption 53 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A destroyed Ukrainian military vehicle sits abandoned on the side of the road near Novokaterynivka on September 2. Hide Caption 54 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Men clear rubble in Ilovaisk, Ukraine, on Sunday, August 31. Hide Caption 55 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian troops leave the rebel-held town of Starobesheve on Saturday, August 30. Hide Caption 56 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A Ukrainian loyalist fighter from the Azov Battalion stands guard on a hill on the outskirts of Mariupol on August 30. Hide Caption 57 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel listens to the news on a transistor radio in the town of Novoazovsk, Ukraine, on Friday, August 29. Hide Caption 58 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian soldiers stop on a roadside as they wait for the start of their march into Mariupol on Wednesday, August 27. Hide Caption 59 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A man opens a box filled with rocket-propelled grenades left by the Ukrainian army in Starobesheve. Hide Caption 60 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel walks through a local market damaged by shelling in Donetsk on Tuesday, August 26. Hide Caption 61 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian servicemen of the volunteer battalion Azov leave for Novoazovsk on August 26. Hide Caption 62 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Pro-Russian rebels escort captured Ukrainian soldiers in a central square in Donetsk on Sunday, August 24. Hide Caption 63 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – People yell as Ukrainian prisoners are paraded through Donetsk in eastern Ukraine on August 24. Hide Caption 64 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel delivers a speech atop a damaged Ukrainian armored personnel carrier in Donetsk on August 24. Hide Caption 65 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – People look at damaged Ukrainian military equipment in Donetsk on August 24. Hide Caption 66 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – The first trucks of a Russian aid convoy roll on the main road to Luhansk in eastern Ukraine on Friday, August 22. The head of Ukraine's security service called the convoy a "direct invasion" under the guise of humanitarian aid since it entered the country without Red Cross monitors. Hide Caption 67 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel holds shrapnel from a rocket after shelling in Donetsk on August 22. Hide Caption 68 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Residents sit in a makeshift bomb shelter during a shelling in Makiivka on Wednesday, August 20. Hide Caption 69 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Dogs play together as a Russian convoy carrying aid supplies stops at a border control point with Ukraine on August 20. Hide Caption 70 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian forces take their position not far from Luhansk on August 20. Hide Caption 71 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Clouds of smoke are on the horizon as Ukrainian forces and pro-Russian rebels clash in Yasynuvata, Ukraine, on Tuesday, August 19. Hide Caption 72 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – An Ukrainian helicopter flies near Kramatorsk on August 19. Hide Caption 73 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian soldiers load a missile during fighting with pro-Russian rebels Monday, August 18, near Luhansk. Hide Caption 74 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Boys play at a refugee camp, set up by the Russian Emergencies Ministry, near the Russian-Ukrainian border on August 18. Hide Caption 75 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian soldiers carry weapons at a checkpoint near Debaltseve on Saturday, August 16. Hide Caption 76 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Pro-Russian rebels greet each other as they pass near Krasnodon, Ukraine, on August 16. Hide Caption 77 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A fireman tries to extinguish a fire after shelling in Donetsk on August 16. Hide Caption 78 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian border guards patrol near Novoazovsk on Friday, August 15. Hide Caption 79 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Trucks of a Russian humanitarian convoy are parked in a field outside the town of Kamensk-Shakhtinsky, in the Rostov region of Russia about 20 miles from the Ukraine border, on August 15. Ukrainian officials were preparing to inspect the convoy, which was bound for the conflict-torn east. Hide Caption 80 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A truck driver from the convoy jumps out of a trailer on August 15. The Ukrainian government had expressed fears that the convoy was a large-scale effort to smuggle supplies or troops to pro-Russian rebels. Hide Caption 81 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A tank belonging to pro-Russian rebels moves along a street in Donetsk on August 15. Hide Caption 82 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A Ukrainian soldier walks past a line of self-propelled guns as a column of military vehicles prepares to head to the front line near Ilovaisk on Thursday, August 14. Hide Caption 83 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A Ukrainian soldier prepares a mortar at a position near Ilovaisk on August 14. Hide Caption 84 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A man inspects damage at his house after a shelling in Donetsk on August 14. Hide Caption 85 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A convoy of trucks, which Moscow said was carrying relief goods for war-weary civilians, moves from Voronezh, Russia, toward Rostov-on-Don, Russia, on August 14. Hide Caption 86 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Pro-Russian rebels on the outskirts of Donetsk stand at a checkpoint near a bullet-riddled bus on Wednesday, August 13. Hide Caption 87 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel inspects damage after shelling in Donetsk on Thursday, August 7. Hide Caption 88 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Smoke billows from a Ukrainian fighter jet crash near the village of Zhdanivka, Ukraine, on August 7. Hide Caption 89 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Residents of eastern Ukraine cry in a hospital basement being used as a bomb shelter August 7 in Donetsk. Hide Caption 90 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ordnance from a Ukrainian rocket launcher shoots toward a pro-Russian militant position in the Donetsk region on August 7. Hide Caption 91 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Relatives of Ukrainian military member Kyril Andrienko, who died in combat in eastern Ukraine, gather during his funeral in Lviv, Ukraine, on August 7. Hide Caption 92 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Refugees from southeastern Ukraine wait at a refugee camp in Donetsk on Wednesday, August 6. Hide Caption 93 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian rebel adjusts his weapon in Donetsk on August 6. Hide Caption 94 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Men walk past a bomb crater in Donetsk on August 6. Hide Caption 95 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A man steps out of his car as Ukrainian soldiers inspect the vehicle at a checkpoint in Debaltseve on August 6. Hide Caption 96 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian servicemen sit on a bus near Slovyansk, Ukraine, on Tuesday, August 5. Hide Caption 97 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A pro-Russian separatist guards a road as Australian, Malaysian and Dutch investigators prepare to examine the crash site of Malaysia Airlines Flight 17 near the village of Rossipne, Ukraine, on August 5. U.S. and Ukrainian officials allege that a Russian-made missile shot down the plane from rebel-held territory, killing all 298 people on board. Russia and the rebel fighters deny involvement. Hide Caption 98 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Rescue workers carry the body of a woman who was killed during a bomb shelling in Donetsk on August 5. Hide Caption 99 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A boy stands in a hallway of a refugee hostel run by pro-Russian rebels in Donetsk on Monday, August 4. Hide Caption 100 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian servicemen from the Donbass volunteer battalion clean their guns Sunday, August 3, in Popasna, Ukraine. Hide Caption 101 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian soldiers fire shells toward rebel positions near Pervomaysk, Ukraine, on Saturday, August 2. Hide Caption 102 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – Ukrainian troops patrol near the village of Novoselovka on Thursday, July 31. Hide Caption 103 of 104 Photos: Photos: Crisis in Ukraine Crisis in Ukraine – A woman says goodbye to her mother as she flees her home in Shakhtersk, Ukraine, on Tuesday, July 29. See more photos of the crisis from earlier this year Hide Caption 104 of 104

Map: Location of Russian convoy

And while hopes diminish for answers about MH17, thousands of people in the region have no access to water, electricity and proper medical aid, humanitarian agencies have said.

The Donetsk water supply was turned off temporarily after the city's water treatment facility stopped operating because ongoing fighting downed power lines. The Donetsk City Council announced on its website that the water supply would be cut off starting at 9 p.m. local time on Sunday (2 p.m. ET).

Ukrainian officials acknowledged Sunday that a convoy of more than 260 Russian vehicles on the border is, in fact, carrying humanitarian aid, a statement on the Ukrainian Cabinet website said.

The convoy initially sparked fears that Russia was trying to use a humanitarian convoy as a cover for sending in more aid and weapons for pro-Russian rebels in eastern Ukraine.

Aid delay likely

But there could be a hold up on the delivery of that aid.

Ukraine received an inventory of the supplies Saturday, which was signed by the head of the regional International Committee of the Red Cross delegation to Russia.

Pascal Cuttat says there are still "basic technical details" that need to be discussed.

The convoy's inspection will not happen Sunday, said Victoria Zotikova, a spokeswoman for the ICRC.

Zotikova added that the aid agency is missing security guarantees from all sides.

Moscow says the trucks contain grain, sugar, baby food, medical supplies and sleeping bags -- a claim that Kiev initially doubted.

The Ukrainian-recognized governor of Luhansk, Irina Verigina, said that she doesn't want aid from Russia.

Ukraine says it is distributing its own aid through the Red Cross.

"They send us tanks and Grads (rocket-launching vehicles) overnight and offer to send humanitarian aid by day," Verigina said.

Ukraine: We destroyed most of a Russian convoy

JUST WATCHED Convoy: Humanitarian aid or Trojan horse Replay More Videos ... MUST WATCH Convoy: Humanitarian aid or Trojan horse 03:56

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Ukraine claims its artillery destroyed much of a military convoy that crossed from Russia into Ukraine last week, an incursion that two British newspaper journalists say they witnessed.

If true, Ukraine's account and the British reports appear to give credence to what Kiev has long alleged -- that Russia has been sending troops and arms into eastern Ukraine.

A diplomatic row was brewing Friday over the reports, with the United Kingdom's foreign office summoning Russia's ambassador in London to explain the incident.

Russia's Foreign Ministry has denied any such incursion, and its foreign minister will meet in Berlin with his counterparts from Ukraine, Germany and France on Sunday, state-run news agency RIA-Novosti reported. The meeting's agenda wasn't immediately released.

Those concerns took on a new light when British media outlets The Guardian and The Telegraph reported that armored personnel carriers, along with other vehicles with Russian military plates, crossed the border near Donetsk.

The Guardian reported that it witnessed 23 armored personnel carriers, in addition to other vehicles with Russian military plates, cross into Ukraine through a gap in a barbed wire fence. "Armed men were visible in the gloom by the border fence as the column moved into Ukraine," the Guardian report reads.

This is the first time foreign media recorded such an incursion, though it illustrates what Kiev has said has been happening for months -- that Russia has been sending troops and equipment to help the rebels, said Lysenko.

Poroshenko told British Prime Minister David Cameron that Ukrainian forces destroyed "the majority" of the Russian vehicles, Poroshenko's office said.

Poroshenko "expressed concern over the situation on the border, particularly over the fact that the inflow of Russian arms and military machines in Ukraine through the open part of the border continued," his office said.

Lysenko said he didn't know exactly how many vehicles crossed the border, or how many Ukraine's artillery managed to destroy.

Battle rages on

A Ukrainian fighter jet was shot down on Sunday in the Luhansk region, Leonid Matyuhin, the spokesman for Ukraine's counter-terrorist operation, told CNN. The pilot managed to eject and is safe, Ukrainian state media reported.

The ongoing fighting -- sparked last year with by political crisis over whether Ukraine would seek closer ties with Europe or Russia -- has left more than 2,000 people dead and just under 5,000 wounded in eastern Ukraine since mid-April, according to estimates from U.N. officials.

The United States and the European Union have applied steadily increasing sanctions against Russian officials, banks and other interests since March, when Russia annexed the Black Sea Ukrainian peninsula of Crimea. Russia's move came a month after Ukraine's parliament ousted pro-Moscow President Viktor Yanukovych.

Yanukovych left office after violent protests against his government in the capital, Kiev. Those protests were motivated in part by his decision to back out of a trade deal with the European Union in favor of closer ties with Russia.