Unidentified gunmen killed two customs officers in western Pakistan, officials said on Sunday, following the killing of five other customs officials in Khyber Pakhtunkhwa’s Dera Ismail Khan in recent days.

No group has claimed responsibility for the two attacks since Thursday, which police said they were investigating.

Security in regions of Pakistan bordering Afghanistan has deteriorated in recent years. Attacks, some claimed by the banned Tehreek-e-Taliban Pakistan (TTP) militant group, have risen, mostly targeting police and security officials.

“Customs officials were present for checks… when unknown persons opened fire,” said the district deputy superintendent of police, Muhammad Adnan, adding that two people were injured and the area on a busy highway had been cordoned off.

“Three days ago, five officials, including an officer, of the customs department, were killed in a shooting in the same area and the attackers escaped,” he said.

The rise in attacks has escalated tensions between Pakistan and the Afghanistan’s ruling Taliban administration.

Pakistan, saying militants have been using Afghan territory to launch attacks, has called on the Taliban to take action and carried out an airstrike last month on Afghan territory.

The Taliban have denied allowing the use of Afghan soil for militancy and said Pakistan’s security issues are a domestic issue for Islamabad.