A suicide bomber on Tuesday night fired his way towards the VIP lounge of the international airport in Islamabad.

He was soon blown as a grenade he hurled exploded near him.

Five security personnel were injured.

Initial reports said that the bomber must have targeted Prime Minister Shaukat Aziz who flew in from Gwader, a small port in Balochistan province, about half an hour before the incident.

However, security officials said Aziz arrived at the nearby Chaklala airbase and the suicide attack was aimed at spreading panic as it followed five such strikes in Islamabad and other parts of Pakistan in the last two weeks.

Police officials said the well armed bomber, who approached the entrance of the VIP Lounge of the airport, tried to force his way firing at the security personnel.

The bomber tried to hurl a grenade that exploded right at his feet killing him on the spot.

Police officer Sayed Marawat Shah told the media at the airport soon after the incident that the bomber had arrived in a rented car. They have arrested the driver of the car which brought the bomber.

Police officials said no damage was done to the airport but it was closed for the time being for flights to take off.

Airport officials, however, said no flights were due at this time of the night.

Some of the police officials said security at the airport was kept very tight on Tuesday following an intelligence tip off that it could be target of a suicide attack.

DIG police of Rawalpindi Mahummad Farooq said the bomber was killed and five policemen were injured in the attack.

The attack was sixth of its kind since January 26, when a suicide bomber blew up at the emergency exit of the J W Marriot hotel hours before Indian High Commissioner to Pakistan Satyabrata Pal held a Republic Day reception. The bomber and a police guard were killed in the attack.

It was followed by suicide attacks in Peshawar in which the city police chief was killed. Later another suicide bomber blew up in Dera Islami Khan in NWFP followed by another suicide attack at an army convoy near the same town in which two army personnel and the bomber were killed.

Security officials attributed the spate attacks as the retaliatory actions by pro-Taliban militants opposing the crackdown in Afghanistan and Waziristan areas.

Pakistan's Interior Minister Aftab Khan Sherpao said the bomber was carrying three grenades, one of which exploded when he tried to throw it.

The remaining two grenades were recovered, he said.