East Timor police and United Nations peacekeepers guarded key buildings in the capital Dili on Thursday, as the government ordered an inquiry into rioting that left at least one person dead.

Many businesses remained closed, a day after student protesters went on the rampage, looting shops and vandalising buildings.

The protesters torched buildings and looted shops

The prime minister's house was among those torched, after what started as a peaceful protest over the arrest of a student turned violent.

It is still unclear exactly what lay behind the rioting.

Prime Minister Mari Alkatiri, announcing an inquiry by a team of MPs, officials and a non-governmental organisation, blamed unidentified "outside influences".

Officials insisted it was not just a student protest which got out of control. East Timor Foreign Affairs official Caroline O'Brien said the protest was disrupted when it was joined by another group which started throwing stones.

Some witnesses said between three and five people were killed, but UN and government forces put the official toll at one. It is not clear whether bullets that were fired during the incident came from the police or the protesters.

President's appeal

There were sporadic clashes on Thursday, but the streets were otherwise calm following an overnight curfew, officials said.

But many feared there would be more violence and Dili's airport was crowded with foreign workers trying to leave. A UN spokesman said the UN had not ordered an evacuation but was providing two planes for those wanting to leave.

President Xanana Gusmao, who came to office when East Timor gained its independence in May, went on the radio to appeal for calm.

"If you burn people's houses and steal their possessions, they will leave," he said. "If they leave, what is going to happen to us?

"We will be alone with our poverty, without help, forgotten."

East Timor is Asia's poorest country and it is still scarred by the violence of 1999 when it voted to break away from Indonesian rule. It became fully independent after nearly three years of UN administration.

The BBC's Rachel Harvey in Jakarta says the rioting may be a result of a "clash between expectations and reality" in the tiny, impoverished state.

The prime minister appeared unfazed by the attack on his home.

"That is my personal house and for me that is not a problem," Mr Alkatiri told reporters. "But there is much more damage in this country."