At least 11 suicide bombers have entered Islamabad and Rawalpindi to target politicians and sensitive installations during the month of Muharram, the local media has reported.

Intelligence agencies issued an alert about the terrorists entering the two cities after receiving a tip-off from the northern areas, sources told The News daily.

Among the likely targets of the bombers, who belong to outlawed militant groups, are former federal ministers Sheikh Rashid Ahmed and Ejazul Haq, the son of late military dictator Gen Zia-ul-Haq, former premier Nawaz Sharif and top police officers, the report said.

The suicide bombers might also target police facilities like the police lines or headquarters of the Federal Investigation Agency or Shia prayer halls and processions organised during Muharram.

The interior ministry has warned security agencies of possible terrorist attacks on police installations and directed them to strengthen security at these facilities.