Karachi, Oct 30 (IANS) Security has been beefed up in this southern port city ahead of the Friday prayers with additional contingents of police and paramilitary Pakistan Rangers deployed at different roads to avert any terrorist incident.

The interior ministry has directed police to strengthen security outside mosques and imambaras for Friday prayers. Surveillance cameras have been installed around key government buildings and sharpshooters deployed on the rooftops of key security establishments, The News reported on its website.

More than 200 foreign nationals were arrested during raids in different areas of the city. Three Tajik nationals were among the detainees, along with Afghans. The arrests were made on the directives of Sindh Inspector General of Police Salahuddin Baber Khatak.

Pakistan has been rocked by a series of suicide bombings this year that have claimed over 400 lives. In the worst of these attacks, 110 people, the majority of them women and children, were killed in a suicide car bombing in the northwestern city of Peshawar on Wednesday.

The attacks have increased ever since the Pakistani security forces launched a major offensive against the Taliban in the South Waziristan region of the Federally Administered Tribal Areas (FATA) along the border with Afghanistan.