Residents of Bujumbura cowered at home as rival armed troops were out in force in the city's streets on Thursday, the day after an attempted coup plunged Burundi deeper into crisis.

Fear and confusion gripped the lakeside capital of the central African nation, with many residents hunkering down in their houses, afraid to go out into streets where it was unclear who was in control, or whose side armed soldiers and police were on.

Bujumbura resident Onasphore Ndayishimiye was one of few who dared make the daunting journey to work on Thursday morning. On the way, he said, he narrowly avoided being shot.

"The police saw me and shot at me. I put my hands up and dived on the ground," said Ndayishimiye who was unharmed, but shaken.

He didn't know whose side the men who shot at him were on, nor why they had fired.

Ngugusony Buyenzi, a 26-year-old mechanic said the night had been terrifying with police and ruling party militiamen terrorising his city centre neighbourhood.

He said police and members of the Imbonerakure -- a pro-Nkurunziza youth wing whose name means 'The Watchmen' or, literally, "Those Who See Far" -- had shot some people including a friend of his who was now in hospital.

"I'm afraid they'll return tonight," Buyenzi said as occasional gunshots echoed through the deserted streets, answered by shouts of "Pierre to the Hague!" from those wishing President Pierre Nkurunziza might be tried by the International Criminal Court.

On Wednesday a senior general declared a coup against Nkurunziza who was out of the country at the time, attending a regional crisis meeting in Tanzania.

But it quickly became clear that the aspiring coup leader, General Godefroid Niyombare, did not have complete control over the armed forces.

- Information war -

Radio and televisions stations became the focal points of armed confrontations between opposing sections of the army and police. In Burundi, the information war is a real war.

Overnight at least three independent broadcasters were attacked, shot up, looted and burned by pro-Nkurunziza forces while gun and rocket fire was exchanged outside the state broadcaster which is protected by members of the still-loyal presidential guard brigade.

Fierce fighting resumed on Thursday at the state broadcaster, with troops supporting the attempted coup saying they had launched a major armoured assault to try and capture the state TV and radio complex.

The soldiers backing General Niyombare had also thwarted Nkurunziza's hopes of returning to Burundi on Wednesday night as they seized control of the airport just outside the city, sending civilian workers home and switching off the runway lights.

Burundi's isolation continued on Thursday with the airport closed and borders shut.

Sporadic gunfire and explosions heard throughout the night intensified before dawn and, as the sun rose over the low-slung lakeside capital, dark plumes of smoke snaked into the clear blue sky, seeming to come from buildings close to the port on Lake Taganyika.

Gunfire next to city hotels caused visitors to dive for cover and few civilians dared to venture out in stark contrast to the previous day when thousands had crowded the streets to celebrate the coup announcement.

Streets were blocked, sometimes by people armed and in uniforms, some by burning piles of tyres.

Even on the main road, the Chausee du Peuple Murundi, there were very few vehicles moving. A Red Cross van raced by. When a police truck approached, people hid.

Presidential guards also protected the headquarters of the ruling CNDD-FDD party, with locals saying Imbonerakure and loyalist factions of the police were deployed alongside them.