Armenians are voting for a new parliament Sunday, four years after the former Soviet state's presidential election ended in deadly clashes between police and opposition supporters.

Opinion polls indicate President Serzh Sarkisian's Republican Party and its ally, Prosperous Armenia, are expected to win a majority of the 131 seats. Unemployment, poverty and Armenia's long-running disputes with neighbors Turkey and Azerbaijan are among the top campaign issues.

So far, this election has been largely calm unlike the 2008 disputed presidential race. However on Friday, some 150 people were injured when gas-filled balloons exploded at an election campaign concert in the capital Yerevan.

Mr. Sarkisian's political party was holding the event, and the president promised a full investigation. It was not immediately clear what caused the explosions, but some reports said it could have been caused by a cigarette lit too closely to the balloons.