An IED attack on a truck heading to an army construction site in Northwestern Pakistan left 11 field workers dead, caretaker Prime Minister Anwaar-ul-Haq Kakar said on Sunday.

The explosive device was detonated in a truck transporting the laborers to the project site in Waziristan, near the Afghan border, according to law enforcement forces in northern Khyber Pakhtunkhwa.

"They were working at an army post that is under construction ... an IED exploded under a vehicle carrying the labourers," deputy commissioner of North Waziristan, Rehan Khattak, said.

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No group has claimed responsibility for the attack so far.

Militant attacks in the country have been on the rise since a ceasefire between the Pakistani Taliban, the Tehreek-e-Taliban Pakistan (TTP), and the government collapsed last year.

Pakistan's rocky northwestern region has long been a hotbed of insurgent activity; this has significantly increased in recent years due to the dire economic situation and the fragile political scene, following the ousting of popular former Prime Minister Imran Khan, which left the government preoccupied with dealing with a rising number of threats.

ISIS also increased its terrorist attacks in Pakistan, claiming responsibility for a bombing last July, which targeted a political party rally for Jamiat Ulema-e-Islam-Fazl (JUI-F) in Pakistan's northwestern Khyber Pakhtunkhwa. The attack left 54 dead and dozens injured. Maulana Ziaullah, a regional head of the JUI-F, was among the killed civilians.

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