The death toll in a fresh wave of violence blamed on political and ethnic tensions in Pakistan's biggest city of Karachi rose to at least 20 on Wednesday, an official said.
Renewed tensions between the Muttahida Qaumi Movement (MQM) and the Awami National Party (ANP), which represent different ethnic communities, have triggered serious fears that the violence could spill over on a wider scale.
"The death toll has risen to 20 with eight more targeted killings overnight in different areas of Karachi," provincial home ministry spokesman Sharfuddin Memon told AFP. The violence erupted on Monday.
The government in Sindh province said it stepped up police and paramilitary patrols in the troubled western and central neighbourhoods to avert further killings. Memon gave no specific reason for the renewed violence in Karachi, but analysts believe conflicting interests of political forces and poor governance trigger routine flare ups.
"Karachi is a big city where crime and corruption is rampant and targeted killings are a convenient cover for criminal mafia to continue their activities," analyst Imtiaz Gul told AFP. "While political parties fight to retain their clout in the city, criminal gangs, involved in organised crimes take advantage of the situation."
Both MQM and ANP have accused each other of killing their supporters, fanning tensions within Karachi that reverberate to the capital Islamabad, where both factions are also members of the federal governing coalition.
In 2010, political violence in Karachi was dominated by flare ups in August after an MQM lawmaker was shot dead and in October on the eve of the election for his successor.
The Human Rights Commission of Pakistan said 748 people -- 447 political activists and the rest civilians -- were killed in targeted shootings in the city last year. Targeted killings in 2009 claimed 272 lives.