KARACHI: A fresh wave of violence blamed on political and ethnic tensions has killed at least 15 people in Karachi, DawnNews reported, adding that incidents of firing continued in the city on Tuesday.

Two people were wounded in an incident of firing in the city's Liaquat National Hospital.

However, AFP quoted officials as saying that at least 12 people were killed in the city overnight.

“At least 12 people were killed in targeted killings, which started Monday evening and lasted late in the night,” Sindh’s home ministry spokesman Sharfuddin Memon told AFP.

Memon said police and paramilitary troops were stepping up patrols in the troubled western and central neighbourhoods to avert further violence.

Among the dead was an MQM activist in Aligarh Bazaar area and local lawyer Zia Alam, a member of the Pakistan People’s Party (PPP).

In 2010, political violence in Karachi was the deadliest for years, 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 says 748 people — 447 political activists and the rest innocent citizens — were killed in targeted shootings last year. Targeted killings in 2009 claimed 272 lives.

Karachi is also plagued by ethnic and sectarian killings, crime and kidnappings.