Dozens of Ukraine’s government troops have been reportedly killed after local militia shelled pro-Kiev military forces with Grad rocket launchers. President Poroshenko has vowed “killing hundreds” for each deceased soldier.

Self-defense troops attacked a Ukrainian military unit at around 5:00am near Zelenopolye village in the Lugansk region, not far from the Russian border, Kiev’s officials reported.

A military official described the consequences of what he called “a bloody terrorist act” as “destruction” saying that about 30 were feared killed.

"About 30 servicemen are thought to have been killed in a shelling by militants using Grad multiple rocket launchers at units of the Ukrainian anti-terrorist operation (ATO) forces near the village of Zelenopolye,” Zoryan Shkyryak, an adviser to Interior Minister Arseny Avakov, said at a briefing. “There might be more victims.”

Фото разгромленных сегодня утром подразделений 24 ОМБр и 79 ОАЭМБр. Жуть полная... pic.twitter.com/oxYWGLpTGr — Военные Фото (@RuPhotoMilitary) July 11, 2014

However, the Ministry of Defense press-office later confirmed the deaths of only 19 servicemen, lowering the initial death toll. It also said that 93 soldiers had sustained wounds, while Shkyryak put the number of injured at 100 people.

Self-defense forces have confirmed that they targeted the Ukrainian army convoy with Grad rocket launchers.

“According to our information, the Ukrainian military convoy from Lvov came under fire. The exact number of killed is unknown; there might be two or three dozen killed. The convoy was destroyed,” a member of the opposition told RIA Novosti.

Speaking in front of journalists, the Interior Ministry adviser vowed revenge for the attack, saying that those behind it “will be punished, either eliminated or captured, and they will answer according to the laws of Ukraine."

Ukrainian President Petro Poroshenko later echoed the retaliation threats, stating that for each of the killed men “militants will pay with dozens and hundreds of theirs [people].”

One of the soldiers’ wives has told the UNIAN news agency that her husband contacted her by phone and said that fighting had started again near Zelenopolye as opposition self-defense troops fired at a military convoy that was transporting servicemen wounded in the morning attack.

The woman, who was not named, told the journalists that pro-government troops have no equipment and ammunition to fire back.

“They really need help and reinforcements,” she told journalists, urging them to pass on the information to Kiev.

Meanwhile, the spokesman for Kiev’s military operation in the east, Vladislav Seleznev, has said that 23 Ukrainian soldiers have died in battle between opposition and government forces in eastern Ukraine in the last 24 hours.

“Twenty-three members of the armed forces of Ukraine and the state border service of Ukraine have been killed, with 93 sustaining injuries. All the wounded are receiving medical treatment," Seleznev posted on his Facebook page.

Seleznev stressed that the death toll figures he shared in his post included the number of soldiers killed on Friday morning.

Confrontations between the two sides in the area close to Russian-Ukrainian border have recently intensified.

“The epicenter of severe confrontation came closer to the state border line,” the Ukrainian State Border control said in a statement on Friday.

In the wake of heavy fighting, Russia has closed three major border crossings: ‘Donetsk’, ‘Gukovo’ and ‘Novoshakhtinsk’ on the Russian-Ukrainian border, according to Vasily Malayev, a spokesman for the Federal Security Service in the Rostov region.

On Thursday, two Ukrainian border control guards were killed and another two were injured near the Dolzhansky border checkpoint.

“This is confirmed information, according to all law enforcement agencies and the Ministry of Defense, and The National Guard, and the border service," the Ukrainian National Guard's information security chief Yury Stets said.

Meanwhile, shelling continues all over the region with Kiev’s troops targeting residential areas.

In the recent attack on Friday, the Ukrainian air force fired rockets at the city of Dzerzhinsk in the Donetsk region and destroyed a cemetery, transformer vault and a gas pipeline.

Watch video footage from the bombed cemetery in Dzerzhinsk

At the same time, opposition in Dzerzhinsk claims it has downed a Ukrainian army jet, according to Itar-Tass.

Another Kiev aircraft was knocked out in the neighboring Lugansk region, the news agency reported.

In the meantime, more civilians are becoming innocent victims of Ukrainian army shelling. In one of the latest tragedies in Lugansk, a woman was killed as a shell landed on her apartment’s balcony.

E. Ukraine's Lugansk: From busy city to ghost town

There are those who have miraculously survived.

RT’s Maria Finoshina met Andrey Girin, who brought his wife to a hospital after their car was fired at.

“I was in the shop and I heard someone scream 'lie down on the ground.' But I yelled that my wife was in the car, so I looked out of the window, saw that she wasn't there and heard her knocking on the shop door,” he said.

The country’s deputy health minister, Vasily Lazoryshynets, said on Thursday that 478 civilians, including seven children, had been killed in Kiev’s military crackdown on the eastern regions of Ukraine – which “is unfortunately greater than the military losses.”

However, the Ukrainian Ministry of Health later reduced the civilian death toll figure, saying that the deputy minister “only provided the latest statistics on the overall mortality level.”