Counting is under way in Northern Ireland’s assembly election, with the first results expected within hours.

It is the second time in 10 months the electorate has been asked to choose a government.

The snap election was called after the resignation of former Deputy First Minister Martin McGuinness over a botched heating scheme debacle.

Official figures indicate turnout was higher than the 55% who voted in May – by 13 percentage points in one area.

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A total of 1,254,709 people were eligible to vote for 228 candidates competing for 90 seats in 18 constituencies.

The turnout was up across the board:

• Mid-Ulster: 72%, up 13 percentage points on 2016
• Strangford: 61%, up 11 points
• North Down: 59%, up 10 points
• Foyle: 65%, up nine points
• East Londonderry: 63%, up 12 points
• Belfast West: 67%, up nine points
• Belfast East: 63%, up six points
• Belfast South: 64%, up 10 points
• Belfast North: 62%, up 10 points
• North Antrim: 63%, up 10 points
• East Antrim: 60%, up nine points
• South Antrim: 62%, up 11 points
• Fermanagh and South Tyrone: 73%, up eight points
• West Tyrone: 70%, up 10 points
• Newry & Armagh: 69% up 10 points
• Upper Bann: 62% up 8 points
• Lagan Valley: 62% up nine points
• South Down: 66% up twelve points

The first declarations are expected within hours, although the final make-up of the new 90-seat Assembly is unlikely to be clear until Saturday afternoon.

Polling stations closed at 22:00 GMT on Thursday and ballot boxes were moved to eight counting centres across Northern Ireland.

Analysis: BBC News NI Political Editor Mark Devenport

The high turnout is evidence people were engaged by this campaign, but it is unclear at this stage what drove them – anger over the renewable heating saga, concern over the Irish language act, or the DUP’s argument that Sinn Féin’s growth might upset the constitutional balance.

We should start getting some idea of the answers to that question as the votes are counted in the hours to come.

By Saturday we should have 90 new MLAs, but before then there will be lots of drama as political careers hang in the balance.

And as soon as the dust settles the Northern Ireland Office will want the politicians to focus on urgent negotiations to try to chart a way forward.

The snap election was called after the collapse of a coalition led by Arlene Foster’s DUP and Sinn Féin’s Martin McGuinness.

Mr McGuinness resigned over Mrs Foster’s refusal to step aside as first minister pending an inquiry into the Renewable Heat Incentive (RHI) scheme, which could cost the Northern Ireland tax payer £490m.

Under Northern Ireland’s power-sharing agreement, the government must be run by Irish nationalists and unionists together.

This assembly election saw one significant change: The number of assembly members has been reduced from 108 to 90 which will mean each constituency returning five MLAs each and not six as was the case beforehand.

The number of MLAs has been cut in order to reduce the cost of politics.

Forty-eight fewer candidates stood in this election than in May last year.

Opinion polls ahead of the election indicated the DUP would lose votes but remain the largest party, followed by Sinn Féin.

An online exit poll by Lucid Talk found that turnout appeared to be 2-3 percent higher among nationalist voters compared to the 2016 election, while turnout for unionist voters was unchanged.

Speaking on RTE’s Morning Ireland, DUP MP Gregory Campbell said: “One big issue that is causing people difficulties in terms of projecting what final outcomes might be is the reduction from six to five in terms of seats per constituency.”

Sinn Féin’s Gerry Kelly said the higher turnout was significant.

“That shows that people are engaged, that they see this election as important,” he told the BBC’s Good Morning Ulster programme.

The SDLP’s South Belfast candidate Claire Hanna said there had been more energy around polling stations, despite “awful” weather later on Thursday.

“That does, historically, tend to favour the centre ground,” she said.

Speaking to the BBC’s The View on Thursday night, former DUP MLA David McIlveen, who lost his seat in May 2016, said this election was “the last-chance saloon” for the DUP.

Mr McIlveen delivered stinging criticism of the two main unionist leaders, Arlene Foster and Mike Nesbitt, saying they had “as much charisma in a bit of tofu” – and even suggested Mrs Foster may no longer be the DUP leader on Monday.

Elections to the Northern Ireland Assembly use a form of proportional representation called the Single Transferable Vote (STV), in which voters rank candidates by numerical preference.

Candidates are then elected according to the share of the vote they receive.

The largest unionist and nationalist parties after the election will have three weeks to form a power-sharing government to avoid devolved power returning to the British parliament at Westminster for the first time in a decade.

The BBC News NI website will carry the latest election results and analysis on Friday and throughout the weekend.

There will also be special election programmes running on BBC Radio Ulster from midday, on BBC Radio Foyle from 15:00 GMT and on BBC One Northern Ireland at 13:30 GMT.