ISLAMABAD, July 11: The US embassy, British and Canadian high commissions and important buildings in the twin cities received threatening telephone calls and messages on Thursday.

According to the police authorities, similar threats were also received at the Canadian High Commission in New Delhi and its consulate in Kolkata.

Security officials said an e-mail message was received by the British High Commission in which the sender said the high commissioner would be murdered and the US embassy would be blown off. The e-mail was received at about 12:32pm on Thursday, police said.

A source close to the police said the message, which was received by the British authorities, identified some people who were planning to target the UK High Commission and the US embassy in Islamabad. After the messages were received, Pakistan’s security personnel carried out a search operation to trace these people, but remained unsuccessful, he said.

An anonymous bomb threat was also received by the Canadian High Commission in Islamabad at 1:35pm on Thursday.

The caller, who did not identify himself, said the Canadian High Commission would be blown off within the next 24 hours. According to the police, the high commission staff did not inform the police about the call till 5:10pm.

Ehsan Saddiq, superintendent of police VIPs and diplomatic protection department, said security at the Diplomatic Enclave had been further tightened after the threat calls.

The SP said the Canadian authorities had expressed their satisfaction over the security measures adopted by the Pakistani authorities.

Meanwhile, in a related development, some people claiming to be Al Qaeda activists called the Federal Public Service Commission officials and said that a bomb had been planted in the building which would detonate soon. The building was immediately evacuated, but after extensive search by the bomb disposal squad, the building was declared safe at 12:55pm.

In Rawalpindi, a similar bomb threat was received at Shalimar Hotel in the afternoon. The hotel was also evacuated, but the call turned out to be a hoax. The hotel is located close to Pearl Continental hotel.