Dozens of people were killed on Wednesday in a suicide bombing near a polling station in the city of Quetta in western Pakistan.

The militant "Islamic State" (IS) group and the Taliban threatened to target voters during Pakistan's national election.

Polls have now closed across the country and ballots are being counted, with initial official results expected early Thursday.

Deadly bombing in Quetta - what we know so far:

• 31 people were killed, including a child, and more than 30 people were wounded when a suicide bomber detonated outside a crowded polling station in Quetta.
• Several of the wounded were in critical condition and the death toll could rise further.
• Local police officials said the suicide bomber tried to target a high-ranking military officer who was part of a delegation visiting the polling station, but due to tight security, he detonated at the gate.
• IS claimed responsibility for the explosion, according to a statement on the group's Amaq news agency. The statement did not provide further details or give evidence for the claim.
• The blast impacted voter turnout in Quetta, with some staying away or trying to vote as quickly as possible, according to a local journalist.

Divisive vote

This year's national election had been dubbed Pakistan's "dirtiest election" following accusations that the military is attempting to interfere with the vote. The leading contenders are Khan and and Shahbaz Sharif, the brother of Nawaz Sharif, who took control of PML-N.

Over 105 million people were eligible to cast their ballots to elect the nation's third consecutive civilian government. Over 11,000 candidates ran for national and provincial posts, according to election authorities.

EU condemns attack

The European Union's election observation mission in Pakistan sharply condemned the suicide blast in Quetta in a statement.

"This is a deplorable and cowardly attack on a day when voters across Pakistan should be casting their ballots in a peaceful environment, without fear or hindrance," Michael Gahler, the EU's chief observer to Pakistan, said.

"Violence must not undermine the elections and the democratic process," he added.

'We're on high alert'

Officials had increased security across Pakistan for the election on Wednesday after deadly attacks in the final weeks of the campaign killed over 180 people, including three candidates. Some 370,000 troops and 450,000 police officers have been stationed at 85,000 polling stations across the country.

"We're on very high alert," an officer told DW's Naomi Conrad in Islamabad.

Baluchistan, the province where Quetta is located, saw some of the worst violence during the election campaign. A suicide bomber at an election rally in the Mastung district killed over 100 people earlier this month. Another 400 people were injured in the attack, which was claimed by IS.

rs,es/se (AP, AFP, dpa, Reuters)