The UN Security Council needs to step up and take action to address the lack of accountability for human rights violations committed in East Timor to ensure there isn't a repeat of the violence that has marred Dili, the nation's capital, in recent years, says Amnesty International.

"On two separate occasions since independence, in 2006 and again in 2008, political violence erupted in [East Timor]," wrote Renzo Pomi, Amnesty's representative at the UN, in a letter dated Tuesday.

"Although there were complex reasons for each situation, the failure to rebuild the justice system effectively and to bring those responsible for past human rights violations to justice contributed to an environment where there was no strong deterrent to political violence and human rights abuses."

With the UN's current mission in the East Timor up for renewal this Friday, Pomi said it's time to tie up loose ends, complete investigations and push ahead with prosecutions for the many human rights violations that occurred during the brutal 24-year occupation by the Indonesian military between 1975-99.

"I am writing to urge the Security Council to take immediate steps to address the continuing lack of accountability for crimes against humanity and other grave human rights violations which occurred in [East Timor] under Indonesia's occupation," wrote Pomi.

A technical assessment of the UN's mission in East Timor, carried out last month, echoed the findings of last year's independent needs assessment of the country's justice sector, added Pomi.

"Both reports identified deficiencies and challenges regarding the rule of law, judicial independence and confronting impunity, inter alia."

More than 100,000 people died through fighting, disease and starvation as a result of the Indonesian occupation. East Timor became formally independent in 2002 but today is still one of the world's poorest nations.