"We have got reports that at least 24 people have fallen victim to targeted killings since Tuesday evening," Sharfuddin Memon, an official of the southern Sindh province's home ministry, told AFP.

He said the police had arrested 12 men with guns and ammunitions for alleged involvement in the targeted killings.

A police surgeon, Hamid Parhiar, said city hospitals had received the bodies of 15 victims.

A security official said tensions in Orangi Town and Qasba areas, where gunmen were still opening fire intermittently, had left streets deserted and markets closed.

"Police and paramilitary troops are on the patrol in the troubled neighbourhoods to avert further violence," Memon said.

The police said five bodies were found on a bus in Gulshan-e-Iqbal area.

"We saw a bus parked suspiciously along a street and found bodies of five people all shot dead inside. Their identities are still unknown," police official Mohammad Hashim said.

Center>Copyright AFP (Agence France-Presse), 2011