Indian High Commissioner Satyabrata Pal was having lunch with his wife at their two-storey India House, located a little more than 200 feet from the Danish embassy, when the explosion shattered almost all window panes of the building.

No one from the Indian mission was hurt in the blast that took place at about 1 PM after a car drove up and stopped outside the embassy in the upmarket Sector F-6/2, where several foreign missions are located.

The explosion, which also left 24 people injured and damaged 30 vehicles, caused a four-foot deep crater in the road and was felt several kilometres away.

No outfit has taken responsibility for the blast that caused extensive damage to the front of the private building in which the Danish embassy was housed. But security officials said the attack could be linked to blasphemous caricatures of Prophet Mohammed published in Danish newspapers that had earned the ire of Muslim world.

Interior Secretary Syed Kamal Shah told reporters that such a link would be part of the probe into the attack.

"It was most likely a suicide blast," Islamabad SSP Ahmed Latif said. Other officials said evidence collected from the site included body parts and ball bearings. Over 30 kg of explosives were packed in the car, they said.

A foreigner, a security guard of the Danish embassy and two policemen were among the dead, the interior ministry said.

A building located opposite the embassy, which housed the office of an NGO, was damaged by the powerful explosion. Several trees outside the embassy were smouldering several hours after the blast. "Bomb that was my first reaction," said Shreedevi Nair-Pal, the wife of the High Commissioner showing a part of the car that had fallen in the premises of India House.

Top officials of the Indian High Commission immediately rushed to the scene to supervise repairs and beef up security at India House. The officials told PTI there were no plans to shift the High Commissioner from the residence in the wake of the attack Several Western embassies located in Sector F-6/2 were evacuated and security was tightened across Islamabad. Hours after the attack, Norway announced it was closing its embassy located close to the Danish mission.

The attack, the second in three months that has targeted foreigners in Islamabad, was condemned by President Pervez Musharraf, Prime Minister Yousuf Raza Gilani, ruling Pakistan People's Party Chairman Asif Ali Zardari and PML-N chief Nawaz Sharif.

A bomb blast at an Italian restaurant frequented by foreigners on March 15 had killed a Turkish woman and wounded 10 foreigners, including four US FBI staff.

Rehman Malik, the advisor to the Prime Minister on Interior Affairs, sought a report on the attack within 24 hours.

Reports suggested that the Danish embassy had been issued several warnings about security threats. Denmark recently downgraded the embassy and moved most foreign staff out of Pakistan.