ISLAMABAD, June 4: The security agency has picked up eight alleged terrorists for their involvement in a plot to assassinate President Asif Ali Zardari during his scheduled visit to Pakistan Institute of Medical Sciences (Pims), sources told on Saturday.

The sources said that the arrest was made after security agency intercepted a call on May 15 in which two terrorists were planning to carry out suicide attack during the scheduled visit of President Asif Ali Zardari to Pims to enquire after his ailing father.

The security agency traced the phone call and succeeded in locating one of the group members, who was arrested from the area of Margalla police station about three week ago.

The alleged terrorist was handed over to the security agency which obtained from him the whereabouts of his other group members scattered in Islamabad and its adjacent areas.

The assassination plan and the arrest was also shared with the president, the sources said.

Later, his other group members were also arrested from Islamabad and its adjacent areas.

During interrogation they disclosed their association with a banned sectarian outfit and admitted that they had planned to assassinate the president.

They said the group had also planned to kill the president in Nawab Shah during his father's funeral prayers or burial, the sources said. In the light of the information, intelligence was mounted at Nawab Shah which led to the arrest of four other alleged terrorists involved in the plot, the sources said.

The sources said the burial of the president's father was all set to take place on the evening of May 25, but due to security risk the ceremony was delayed till next morning and during the period the four alleged terrorist were arrested.

The security agency has also picked up over two dozens other people for their alleged links with the group, the sources said.

The names of the alleged terrorists were being kept secret.