Dozens of Afghans were killed or wounded in poll-related violence Saturday as the legislative election turned chaotic with hundreds of polling centres failing to open and voters queueing for hours due to technical glitches and lack of staff.

Election organisers, who have been skewered over their shambolic preparations for the long-delayed ballot, extended voting until Sunday for 360 polling centres after hiccups with voter registration lists and biometric verification devices caused lengthy delays.

At least three people were killed and more than 30 wounded in multiple explosions across Kabul, acting health ministry spokesman Mohibullah Zeer said, after the Taliban warned voters to boycott the ballot "to protect their lives".

The Italian NGO Emergency said 37 people had been taken to its trauma hospital in Kabul, including a dead child.

An Independent Election Commission (IEC) employee was killed and seven others were missing after the Taliban attacked a polling centre in the northern province of Kunduz, destroying ballot boxes, provincial IEC director Mohammad Rasoul Omar said.

Three rockets also struck the Kunduz provincial capital, but there were no casualties.

The Taliban claimed it carried out 166 attacks on voting locations, checkpoints and military sites on Saturday morning.

Despite the threat of violence, large numbers of voters showed up at polling centres in major cities where they waited hours for them to open. (AFP)