A Pakistani anti-terrorism court judge and his three family members were killed in an ambush while traveling in Pakistan, police announced Sunday.

Aftab Afridi, the slain judge, and his family were traveling to the capital Islamabad when their vehicle was ambushed by the assailants near Swabi district, located some 51 miles (82 kilometers) from Peshawar, the capital of northwestern Khyber Pakhtunkwa province, which lies near the border with Afghanistan.

Afridi, his wife and two children – including his two-year-old son – were killed in the attack, police official Shoaib Khan said.

Afridi had been assigned to the anti-terrorism courts in Swat two months earlier. He was hearing several terrorism-related cases as the lead judge of an anti-terrorism court in the scenic Swat valley, once the hotbed of militancy.

Two bodyguards of the judge were also injured in the ambush, police said. The attackers managed to flee.

The police are investigating the possible motives behind the attack, Khan told reporters, adding that the incident seems to be the outcome of an "old enmity."

The judge's family, according to him, have accused their rivals of being involved in the attack.

Prime Minister Imran Khan condemned the incident on Twitter, assuring the family that the perpetrators of this "gruesome" act will be apprehended and dealt with the full "severity of the law."