Grenades were thrown at the Saudi Arabian consulate in Karachi, Pakistan by two unknown assailants on a motorcycle on Wednesday in what might be the first violence response to the killing of Osama bin Laden in the country last week.

A Karachi police officials told media that security guards at the consulate fired back at the attackers, but they escaped.

According to reports, there were no casualties or damage at the consulate which is one of the most heavily fortified buildings in the city.

“There were no casualties. We are seeing this incident in the present context. It could be a reaction of the Osama incident,“ a Pakistani official told reporters.

A photographer from Agence France Presse said the consulate was quickly surrounded by ambulances, police and paramilitary Rangers after the attack.

After this incident we have stepped up security at all foreign consulates in Karachi, a senior police official said.

No one has claimed responsibility for the attack and the link to the bin Laden killing has not been definitively established.

However, Pakistani authorities are currently holding three of bin Laden’s wives (who are from either Saudi Arabia or Yemen) in custody. The US has asked Islamabad to extradite them so investigators can question them about bin Laden and al Qaeda operations.

Moreover, many Pakistanis think that the Saudis finance terrorist groups in Pakistan.

We are expecting some retaliation for the death of Osama bin Laden and we are investigating if this failed attack was part of that, said another police official.