KARACHI, Pakistan - Two blasts in Pakistan's southern city of Karachi killed three people near the office of a political party critical of the Taliban, a police officer said, heightening tensions ahead of the country's historic election next Saturday.

Police officer Aamir Farooqi said the explosions late Saturday wounded 22 people. A spokesman for the Taliban, Ahsanullah Ahsan, claimed responsibility.

Pakistan has been experiencing a wave of violence connected to the elections, mostly at the hands of Taliban extremists targeting various political parties and their candidates. The vote will be the country's first transfer of power from one elected civilian government to another.

Farooqi said the explosions went off near the offices of the Muttahida Qaumi Movement, the biggest political party in the city. It is one of three liberal, secular parties that have been targeted by the Taliban across the country, likely linked to their support for military action against extremists who operate from Pakistan's tribal areas bordering Afghanistan.

It was the second day in a row that the Muttahida Qaumi Movement found itself under attack. On Friday, gunmen riding on a motorcycle killed a prominent activist from the party.

Also on Friday in Karachi, gunmen riding a motorcycle shot to death a parliamentary candidate from the Awami National Party and his 6-year-old son.

The Awami National Party has been repeatedly targeted by the Taliban because of its opposition to the extremists.

No one claimed responsibility for the Friday attacks.