Polls on the Pacific island chain of Bougainville closed on Saturday to end two weeks of voting in a historic referendum on independence from Papua New Guinea.

Officials anticipated the “vast majority” of 207,000 registered voters cast their ballots across the region and beyond, with polling stations established for Bougainvillean diaspora in Australia, the Solomon Islands and other parts of PNG.

“We won’t have turnout figures until the end of the scrutiny process but during polling we witnessed long queues at polling places, we witnessed great enthusiasm,” said chief referendum officer Mauricio Claudio.

“So we anticipate a high turnout.”

The vote is a cornerstone of a 2001 peace deal that ended a brutal decade-long war between Bougainville rebels, PNG security forces and foreign mercenaries that killed up to 20,000 people and displaced thousands more.

Joyous scenes marked the opening of polling stations two weeks ago, with Bougainvilleans asked to choose between greater autonomy or independence from PNG.

There are no reliable exit polls, but it is widely expected voters will return a result in favour of independence.

The last postal votes were due to be collected on Saturday evening, when polls officially closed.

This kicked off a process of verification before counting takes place, with results expected to be announced in the coming week.

If voters do choose independence, the decision would require ratification by the PNG parliament, whose recently installed Prime Minister James Marape will need to carefully manage expectations within the diverse country.

There is anxiety among some in Port Moresby that Bougainville could set a precedent and spur other independence movements.

But rejection risks rekindling old feuds and skittling the peace process.

New Zealand lead an international unarmed police contingent for the vote, backed by fellow witnesses to the 2001 peace agreement: Australia, Fiji, Solomon Islands and Vanuatu.

Claudio said voting had gone “better than we expected” with little incident.