ISLAMABAD, June 27 (Xinhua) -- At least three security personnel were killed in a terrorist attack on Rangers installation in Pakistan's southern port city of Karachi, a police official told Xinhua on Saturday.

The incident happened at around 8:10 p.m. local time (1510 GMT), when a group of terrorists rammed their explosive-laden vehicle into the main gate of the Rangers building near the Gulistan-e-Jauhar area in Karachi, Sindh Inspector General Javed Alam Odho said.

He added that four terrorists were killed in an exchange of fire between the forces and the terrorists.

The security personnel deployed at the gate responded swiftly and effectively, preventing the attackers from fully breaching the facility, said the police official.

Following the incident, a heavy contingent of police reached the spot. A clearance operation is currently underway in the area.

No group or individual has claimed the attack yet.

Sindh Chief Minister Syed Murad Ali Shah has directed authorities to take all necessary measures to arrest the culprits. ■