Three members of Pakistan's paramilitary Rangers force were killed and four others injured after militants attacked a regional Rangers headquarters in the southern port city of Karachi, the military said Sunday.

According to officials, one attacker drove an explosives-laden vehicle into the Rangers headquarters on Saturday night, triggering a fierce gun battle with security forces.

In a statement, the military said security forces killed three attackers and captured a fourth suspect, who was injured. It identified the arrested suspect as an Afghan national.

Security operations were continuing in the area, the military said, adding that Pakistan would retaliate against those behind the attack.

Pakistan has carried out airstrikes inside Afghanistan in recent years, saying they targeted militants responsible for attacks in Pakistan. However, the Afghan government has repeatedly denied allowing militant groups to use its territory to launch cross-border attacks.

The militant group Jamaat-ul-Ahrar, a breakaway faction of the Pakistani Taliban, claimed responsibility for the attack.

The military alleged that the group was acting as an Indian proxy but did not provide evidence. India did not immediately comment on the claim and has denied similar allegations in the past.

President Asif Ali Zardari paid tribute to the three Rangers personnel killed in the attack, expressed sympathy to their families and wished the injured a speedy recovery.

Prime Minister Shehbaz Sharif also condemned the attack and praised security forces for successfully repelling the assault.

Pakistan has seen a rise in militant attacks targeting police and security personnel in recent years.

The military said operations were still underway to track down and eliminate any remaining attackers or their accomplices.