A powerful roadside bomb targeting a police vehicle killed three officers in northwestern Pakistan on Wednesday, police said, marking the third such attack in as many days.

Axar.az informs, citing AP, the blast occurred in Dera Ismail Khan, a district in Khyber Pakhtunkhwa province near the Afghan border, police official Sajjad Khan said. He gave no further details, saying only that an investigation was underway.

No group immediately claimed responsibility for the attack, but Interior Minister Mohsin Naqvi in a statement blamed the Pakistani Taliban for the attack.

The Pakistani Taliban, known as Tehrik-e-Taliban Pakistan, is separate from but allied with Afghanistan’s Taliban government. The group has intensified its campaign against security forces in recent years.