
Khalifa Hiftar attends a military parade in the eastern city of Benghazi in May last year

Violence has erupted in northwestern Libya as the rebel army commander Khalifa Hifter ordered his troops to march on Tripoli.

The U.N. Secretary General Antonio Gutteres was left dismayed on Friday night as Hifter rejected his calls for peace and surrounded the capital of the oil-rich north African state.

On Saturday morning exchanges of fire were reported on roads south of the coastal city as the self-styled Libyan National Army pushed north into the suburbs.

Hifter's army - based in the east - had pushed westward to circle the territory controlled by U.N.-backed Presidential Council and Government of National Accord (GNA) and supporting militias.

A well-informed U.N. diplomat said late Friday that Hifter's forces were reported to be on the outskirts of Tripoli, around 20 miles out, with gunfire close to Tripoli International Airport.

On Saturday the rebel army were said to have made their way into the suburbs just 10 miles from city centre, according to Sky News Arabia.

Local media reported that pro-GNA militias in the Ain Zara suburb were laying down arms and surrendering to the LNA.

The Ministry of Health has declared a state of emergency across all Tripoli hospitals, according to the Libyan Observer, as locals report skirmishes on the outskirts of the city.

The GNA has reportedly carried out airstrikes on LNA positions to the south of the city and declared a no fly zone, saying it will shoot down any rogue aircraft on sight.

A military vehicle of Misrata forces, under the protection of Tripoli's forces, is seen on the road of Wadi al Rabih south of Tripoli, Libya on Friday

This grab obtained from a video published on the Libyan National Army's propaganda page on Friday purported to show troops moving on highways towards the capital

Video purportedly shows heavy clashes in Ain Zara in Tripoli with a high calibre machine gun mounted on the back of a truck unloading rounds down the highway

Men of the LNA pose in celebration after reportedly entering the city of Surman on the northwestern coast, around 40 miles from the capital

Hifter ordered his forces to march on the capital, saying in an audio recording posted online: 'We are coming Tripoli, we are coming.'

He also urged his forces to enter the city peacefully and only raise their weapons 'in the face of those who seek injustice and prefer confrontation and fighting.'

Russia has spoken of their deep concern with the escalation after denying support for the Libyan general when questions were raised over Moscow's intentions in north Africa on Friday.

The Kremlin spokesman Dmitry Peskov said he hoped the crisis would not lead to 'renewed bloodshed', adding that Moscow did not support Hiftar.

Asked if Russia considered supporting Libya militarily, Peskov said: 'No, Moscow is not taking part in this in any way.'

Militias from the western cities of Zawiya and Misrata, which control Tripoli, said they had mobilized to confront Hifter on Friday.

'We are the revolutionaries and the elders ... we declare we are in full mobilization and war,' they said in a video statement posted online.

A group of allied militias called the Joint Tripoli Protection Force based in the area around the Libyan capital announced they would also deploy to repel Hifter's offensive.

Over 100 of Hifter's soldiers were captured by Zawiya militias, said army spokesman Ahmed al-Mesmari. He said the soldiers' commander was being investigated.

LNA video showed heavily armoured vehicles including tanks and trucks mounted with high calibre machine guns purportedly rolling toward Tripoli in video posted on Friday

LNA trucks mounted with heavy machine guns were seen across the highway in a video posed to their Facebook page

Libyan National Army Forces stand at ease in this propaganda footage taken from their Facebook page

Men of the Libyan National Army march on roads south of Tripoli as their commander urged them to enter the city peacefully if possible

Secretary General of the United Nations Antonio Guterres departs from Bengazi Airport, in Benghazi, Libya on Friday night after failed peace talks with Commander Khalifa Hifter

Anti-Hifter activists on social media posted pictures of what they described as militiamen from Zawiya capturing dozens of Hifter's forces and armored vehicles carrying stickers reading '106th Battalion.'

The unit is known to be commanded by Hifter's son, Khaled. It's one of the largest units Hifter has deployed to march on Tripoli.

Also, Misrata militias launched an airstrike targeting Hifter's position at the foot of the mountains of Nafusa, he said. He didn't elaborate on the number of casualties.

In Tripoli, council member Mohammed al-Ammari spoke from the city center saying that Libya will not become a 'hostage in hands of a military dictator once again.'

There were conflicting reports during the day as to how much and where exactly Hifter's fighters were advancing in areas such as Souk al-Khamis.

Video stills showed a man waving to the LNA forces as they claimed they were heading towards the capital

Under the command of Khalifa Hifter the armed forces are reportedly in the suburbs of the capital on Saturday morning with small arms fire reported at the disused Tripoli International airport on Friday

Footage captured on the LNA's propaganda page showed hundreds of men travelling in convoys on highways towards Tripoli

Clashes erupted at night in the western district of Qasr Bani Ghashir, close to Tripoli International airport, which was destroyed in 2014 fighting. Former lawmaker Abdel-Raouf al-Manaei said the forces fighting under the umbrella of the Government of National Accord will not permit 'a replica of el-Sissi military rule in Libya,' in reference to the authoritarian Egyptian President Abdel-Fattah el-Sissi, who is an army chief turned president.

The renewed fighting came a day after U.N. Secretary General Antonio Guterres arrived for his first visit to Libya as U.N. chief.

On Friday, Guterres went to the eastern region, which is the seat of a rival administration and parliament that Hifter is aligned with.

Guterres met with Agila Saleh, head of the east-based parliament, according to spokesman Abdullah Ablahig.

Local militamen, belonging to a group opposed to Libyan strongman Khalifa Hiftar, stand next to vehicles the group said they seized from Hiftar's forces at one of their bases in the coastal town of Zawiya, west of Tripoli

A local militaman, belonging to a group opposed to Libyan strongman Khalifa Hiftar, stands on an armoured vehicle the group said they seized from Hiftar's forces at one of their bases in the coastal town of Zawiya

'I am leaving Libya with heavy heart and deep concern,' he told reporters at the airport shortly after meeting with Hifter.

'I still hope, if possible, to avoid armed confrontation around Tripoli,' he said. 'The United Nations remains available to facilitate any political solution.'

Since Gadhafi's ouster, Libya has been split between rival governments in the east and the west and an array of militias fighting over power and oil fields. Hifter has recently seized much of southern Libya without fighting.

Several governments and organizations urged de-escalation, including those known to be Hifter's key backers, such as France and the United Arab Emirates, without specifically mentioning the commander.