Police in the Pakistani city of Karachi say at least five people have been killed by unidentified gunmen in the city's eastern district.

The police say the victims were members of a breakaway faction of the MQM party.

Reports say the killings provoked clashes in the area between members of the rival factions as groups of youths rampaged through the streets setting cars on fire.

Dozens of people have been killed in Karachi in recent months because of the fighting between the opposing groups.