Sri Lanka's main ethnic minority Tamil party says government troops have attacked its political meeting in the country's former war zone in the north.

Lawmakers from the Tamil National Alliance said Thursday dozens of soldiers armed with sticks attacked a group of supporters in the main town of Jaffna, ahead of local council elections scheduled for next month.

They said the party, which has emerged as a major political force in the north since the end of the 25-year civil war in May 2009, has lodged a complaint with local police.

Tamil Tiger rebels, who were fighting for an independent state for the Tamils, were defeated in the conflict. More than 7,000 civilians are believed to have died during the Sri Lankan army's final offensive and at least 80,000 civilians are estimated to have been killed during the war.

Sri Lanka's government is under intense international pressure to investigate allegations of atrocities committed during the conflict's final stage, after videos containing alleged war crimes surfaced recently.

The latest documentary “Sri Lanka's Killing Fields” aired Tuesday in Britain. Foreign Office Minister Alistair Burt said he was shocked by the “horrific scenes” in the video, which contained footage of what appeared to be the execution of prisoners by government troops.

But Sri Lankan authorities say the video was fabricated, and they deny charges that the government violated human rights and humanitarian law. The government has accused the U.N. and the international community of being duped by a “disinformation” campaign orchestrated by the remnants of the Tamil Tigers.