Fierce fighting has killed an estimated 272 people in recent days in South Sudan’s capital, Juba, as an increasingly tense security situation threatened to send the young country back to all-out civil war.

Al Jazeera staff in the city on Sunday heard loud booms, characteristic of heavy weapons, and gunfire coming from the area near the airport, which local sources said had closed.

In a post on Twitter, Kenya Airways said they had suspended flights to Juba “due to [the] uncertain security situation”.

Gunfire had earlier been heard in the capital’s south-west near an army barracks and a United Nations base.

Information Minister Michael Makuei Lueth said the government “is in full control of Juba right now except [the parts controlled by] the SPLM IO”, referring to the armed opposition group.

Violence from Thursday to Saturday killed mostly soldiers from different armed factions, after gun battles broke out across Juba.

A witness told the Reuters news agency on Sunday that gunfire could be heard in the Gudele and Jebel suburbs, near a military barracks that hosts troops loyal to the country’s vice president Riek Machar.

“There were some loud booms, audible from 10km away,” Al Jazeera’s John Hendren, reporting from Juba, said, referring to the fighting in Jebel.

“It involved tanks, small arms fire and helicopter gunships, so it appeared to be a pretty massive confrontation.”

Lueth said: “We want to save the lives of the people of South Sudan. At this moment, we are not able to lose more lives because these are the people for whom we fought for.

“What happened today was also an unfortunate situation, and we will continue to investigate and find out,” he added.

William Gatjiath Deng, a spokesman for Machar’s military faction, told the Associated Press news agency: “Three helicopter gunships have just come now and bombed our side.”

The fighting on Friday began outside the presidential compound as President Salva Kiir was meeting with former rebel leader Machar and soon spread throughout the city.

An Al Jazeera correspondent later saw bodies of soldiers on the lawn in the compound, but was forbidden from filming them.

Deng said on Saturday the fighting had happened near the presidential compound, known as the State House, and in an army barracks.

“In the morning we collected and counted 35 (dead) from the SPLM-IO (Machar’s faction) and 80 people from the government forces,” he was quoted as saying by Reuters.

Local broadcaster Radio Tamazuj put the number of total deaths at 146.

Our correspondent said the latest bout of violence meant “that the hopes of peace were dimming” in the country, which reached its fifth independence anniversary on Saturday.

“These are not good times," Hendren said on Sunday.

“Two days ago, the presidential palace was struck – that is a major strike into the heart of government here and shows just how shaky it is.

“And on Saturday, the fifth Independence Day was completely silent because Juba was shut down – it was militarily occupied, which is exactly the opposite of what is supposed to happen here under a peace accord in August.”

South Sudan was founded with optimistic celebrations in the capital on July 9, 2011, after it gained independence from Sudan in a referendum that passed with close to 100 percent of the vote.

The country descended into conflict in December 2013 after Kiir accused Machar, his former deputy who he had sacked earlier that year, of plotting a coup.

Civil war broke out when soldiers from Kiir’s Dinka ethnic group disarmed and targeted troops of Machar’s Nuer ethnic group. Machar and commanders loyal to him fled to the countryside, and tens of thousands of people died in the conflict that followed. Many civilians also starved.

A peace agreement signed in August collapsed and fighting continues in many parts of the country, despite both leaders joining a unity government two months ago.

•Source: Al Jazeera and agencies. Photo shows South Sudan troops at a parade.

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