Sinn Féin is the largest party at council level in Northern Ireland.
It is the first time a nationalist party has come out as the largest in Northern Ireland at council level.
It follows last year's Assembly election which also saw the party come out on top.
Sinn Féin vice president Michelle O’Neill hailed a “momentous” result.
As the count stretched into Saturday evening, the republican party had 137 elected councillors by 6.45pm, with gains achieved across the region.
The DUP has 117 council seats, the Alliance Party 62, the Ulster Unionists 52 and the SDLP 37, with 32 others.
DUP leader Sir Jeffrey Donaldson insisted that his party had polled strongly.
Sinn Fein has secured 30.9% of first preference votes so far, ahead of the DUP on 23.3%, 13.3% for Alliance, 10.9% for the Ulster Unionists and 8.7% for the SDLP.
The turnout for the election was 54%.
Six of the 11 council areas have now completed their count.
Sinn Fein has emerged as the largest party in Mid Ulster, Derry and Strabane and Armagh, Banbridge and Craigavon.
The DUP will be the largest grouping in Lisburn and Castlereagh, Mid and East Antrim and Ards and North Down.
Sinn Fein is also leading the race to be the largest party in Belfast.
Alliance has made gains and could become the third largest party in local government.
Veteran PUP councillor Billy Hutchinson became the second party leader to lose his seat in Belfast, following Green Party NI leader Mal O’Hara’s failure to get elected.
The votes are being counted through the single transferable vote system, with 462 seats to be filled across 11 council areas.
The general pattern around voter turnout appeared to be up slightly in areas which would be regarded as predominantly nationalist/republican and down slightly in areas viewed as unionist majority.
It is the first electoral test for the parties since last year’s Assembly elections and takes place against the backdrop of the Stormont stalemate, with the power-sharing institutions not operating as part of a DUP protest against post-Brexit trading arrangements.
Sinn Fein’s Stormont leader Michelle O’Neill described the results as “momentous”.
“It has been a very positive campaign, a very engaging campaign. People have very much engaged,” she said.
“It was about positive leadership, it was about a restoration of the executive, it was about making politics work, that has resonated with the electorate and they have come out in such strong numbers that we are now on course to have a very momentous election result.
“It is now obviously about what we are going to do next. In my opinion we need to double down in terms of getting an executive restored and getting our councils up and running again.
“But those councils will always do better when they are working in tandem with the locally elected ministers who support councils.”
Visiting the local government election count at Belfast City Hall, DUP leader Sir Jeffrey Donaldson said: “If you actually look at the real results rather than the spin that some commentators are trying to put on it, the DUP has increased its share of the vote from last year and we’re on course to win a lot of seats across all the councils.
“We have made gains in a number of councils.
“The DUP has polled strongly in this election despite everything that’s been thrown at us, despite the challenges we’ve faced, the DUP vote has held up well.”
He put the rise in the Sinn Fein vote down to the “collapse of the SDLP”.
Ulster Unionist leader Doug Beattie said he was disappointed at his party’s results.
“Of course I am disappointed. It has been a difficult election, at times it has been a brutal election,” he told the BBC.
He said: “We have lost some long-standing councillors, but we have also brought through some new fresh faces which is encouraging.”
He added: “It does take time, I said this when I took over as the party leader.
“I have been party leader for two years only, we have stuck with the same message for the last two elections and yes we haven’t had successes but we are in the first election cycle of my leadership, it is going to take more than one.
“We need to stick with it, we need to be inclusive, we need to be reaching out to as many people as we possibly can.”
SDLP leader Colum Eastwood said Sinn Fein had “cannibalised” the nationalist vote.
“It has been very clear when we have been speaking to people that people are really annoyed at the DUP, that they want the executive back up and running and they wanted to send a message.
“Sinn Fein asked them to send that message, and they sent it.
“They (Sinn Fein) have totally cannibalised much of the nationalist electorate.
“They were given a good hand and, to be fair, they played it very well, they ran a very good campaign and they deserve the victory they have today.
“Of course the DUP had as their first priority in their election literature to get back to Stormont, let’s see them put their money where their mouth is.”
Northern Ireland’s councils are responsible for setting rates, planning and waste collection as well as leisure services and parks.
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