Gunmen killed at least 25 people in Pakistan's southern port of Karachi, raising tensions as voters cast ballots Sunday in a by-election to replace an assassinated lawmaker.
The violence broke out Saturday night when gunmen opened fire in several parts of the city. Police say they have arrested at least 20 suspects in connection with the killings.
The election was being held to replace provincial lawmaker Raza Haider, a member of the MQM party, who was shot to death in August. The assassination sparked four days of violence that killed at least 85 people.
MQM largely represents the Urdu-speaking community. The rival ANP party represents ethnic Pashtuns. Both parties blame each other for the violence that erupted after Haider's death.
Karachi has been plagued by ethnic and sectarian killings, crime and kidnappings.
Some information for this report provided by AP and Reuters.
