Indonesians kicked off voting on Thursday in parliamentary polls, although the start of elections seen as key to shaping further reforms in Southeast Asia’s top economy was marred by overnight violence in Papua.

The election atmosphere in Papua, in the easternmost part of the country where polling stations opened first, was tense.

Police said at least six people died and a string of buildings, including a university in the provincial capital Jayapura, were set ablaze after attacks on several police posts by gunmen and by a crowd with bows and arrows and hurling petrol bombs.

“The gunmen and other groups tried to make the elections fail,” Papua Police Chief Bagus Ekodanto said, calling for calm.

Tensions in Papua, where a separatist movement has simmered for decades, have been running high in recent weeks and some Papuans have called for a boycott of the election.

Indonesian President Susilo Bambang Yudhoyono’s Democrat Party is tipped to win the most seats in the parliamentary poll, lifting its share of the vote from 7.5 percent in 2004 to as much as 29 percent, according to one recent poll.

That would pave the way for Yudhoyono, a reform-driven ex-general, to run for re-election in the July presidential poll, most likely with a stronger mandate to continue his pro-investment policies of reducing graft and shaking up institutions such as the judiciary, civil service, and police.

The first indications of the winner may come within a couple of hours of polling stations closing at midday in a quick count to be taken from a sample of polling stations.

The parliamentary elections are seen as referendum on Yudhoyono’s performance, particularly when it comes to clamping down on corruption and reviving economic growth.

Yudhoyono, who has an approval rating of 45-52 percent according to recent opinion polls, was Indonesia’s first directly elected president and the first to serve a full five-year term since the autocratic Suharto was forced to step down in 1998.

His administration has delivered stronger economic growth and brought relative peace and stability to the world’s most populous Muslim nation, which also has sizeable religious minorities.

But tackling endemic graft in one of the world’s most corrupt countries has proved far tougher.

Several high-profile officials, including central bankers, have been investigated and imprisoned but some Indonesians feel the worst offenders, particularly the powerful, escape punishment.

The parliamentary elections are a massive exercise in democracy, with more than 170 million eligible voters scattered across a vast archipelago of some 17,000 islands.

After the overnight violence, a polling station in Heram subdistrict in Papua’s provincial capital Jayapura had opened and appeared ready although no one was immediately voting, a Reuters photographer said.

In another polling station in Nabire, west of Jayapura, voting had started although an official said it might be delayed since only 55 ballot papers had arrived for 576 eligible voters.

The elections have seen glitches in distributing ballot papers, ensuring the electoral registers are correct, and educating the public about the process when they vote on ballot papers the size of a broadsheet newspaper.

Because of time differences, voting kicked off in Papua and Maluku, also in Indonesia’s east.

Polling stations open in areas such as the resort island of Bali and the capital Jakarta over the next couple of hours, and close at midday.