A Saudi diplomat was killed in a drive-by shooting near the consulate in Karachi on Monday, the second attack on Saudi interests in Pakistan’s biggest city in less than a week, officials said.

The motive of the attack was not immediately clear, but authorities said they were investigating whether it was connected to the death of Saudi-born Osama bin Laden, who was killed by US forces in Pakistan on May 2.

An official from the media section of the Saudi embassy identified the man as a Saudi diplomat. Karachi police named him as Hassan al-Khatani.

Pakistani police told AFP that the Saudi had been driving a vehicle with diplomatic plates when two motorcycle riders unleashed a hail of gunfire at a crossroads in the city’s upmarket Defence neighborhood.

"The consulate employee died of multiple bullet wounds on the spot," said Fayaaz Leghari, the police chief of southern province Sindh, of which Karachi is the capital.

"The attackers fled on the motorbike," he added.

"At this moment, we can’t say who killed him," Leghari said.

Provincial home ministry official Sharfuddin Memon identified the dead man as a junior officer at the consulate.

"We are investigating if it was linked to the Abbottabad operation or was an isolated incident," he said.

Last Wednesday, drive-by assailants threw two grenades at the consulate in Karachi in what officials said could have been reaction to bin Laden’s death.

But there was no claim of responsibility for the attack.

The Taliban, blamed for some of the worst acts of violence in Pakistan, last Friday claimed a double suicide bombing that killed 89 people outside a police training centre as their first revenge for bin Laden.

Saudi Arabia condemned the grenade assault a "terror attack" and said it had "full confidence" in Pakistan’s ability to arrest the assailants, bring them to justice and provide the necessary protection to the Saudi mission.

Pakistan has been in the grip of domestic and international crisis since US Navy SEALs flew in, seemingly undetected, from Afghanistan to identify and kill the Saudi-born Al-Qaeda terror mastermind at a suburban compound two weeks ago.

Pakistanis have expressed horror at the perceived impunity of the raid, furiously asking if their military was too incompetent to know he was living in a garrison city near the capital, or, even worse, conspired to protect him.

Saudi Arabia expelled bin Laden in 1991 and later revoked his nationality. The government in Riyadh, which is allied to the authorities in Islamabad, last week welcomed his killing as a boost to international anti-terror efforts.

Pakistan is holding in protective custody three of bin Laden’s widows, who come from Saudi Arabia and Yemen, and 13 of their children.