The Sri Lankan government has claimed victory in key provincial elections in the east of the island.

It says the win is a major boost for its war against the Tamil Tigers.

Election officials have confirmed that the government and its allies are on track to win control over a 35-member provincial council in the east coastal region.

But local and international election monitors say they've observed a number of irregularities at polling stations across the eastern districts.

Head of the People's Action for Free and Fair Elections, Kingsley Rodrigo, says voters were threatened and intimidated by members of the pro-government TMVP, a party comprising Tamil Tiger defectors.

"Some of the polling agents were chased off and they intimidated the voters and the voters were not allowed to cast their vote properly. And these allegations were made by various political parties as well as the people. So there were 83 complaints we received yesterday."

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