Rioting forced staff working for the Irish relief agencies GOAL and Concern to abandon their offices in the East Timorese capital, Dili, and move to a UN-guarded safehouse.
A curfew has been declared following the violence and looting which has led to the deaths of up to six people.
It is understood the arrest of a student sparked riots by hundreds of youths. Local police backed by UN police and peace-keeping troops have brought the city back under an uneasy calm.
GOAL's East Timorese director, Ms Anne McGuire, told ireland.comfrom Dili that thousands of people had tried to gain access to the agency's office to get away from the rioting. The house of Prime Minister Mr Mari Alkatiri has reportedly been burnt down.
"Our office is only 400 meters from the parliament building which was attacked by rioters. They then seemed to split and groups went in different directions burning and looting shopping centres and hotels where the expatriate community spends time.
"They threw rocks and petrol bombs at the restaurant beside our building, smashing all the windows and looting the place.
"We were locked into our offices when they turned on the GOAL offices but our security staff went outside and explained that our organisation is not international and not UN so thankfully they moved on."
Ms McGuire said two GOAL international staff are also in the safe house and also four Concern staff including Irishwoman Ms Galye Moffatt .
She added that while gunshots and helicopters could be heard earlier in the day the city was now "eerily quiet".
