MUZAFFARABAD: At least three labourers were killed and 10 others, including two Chinese engineers, were wounded Monday when a blast occurred inside a tunnel at a construction site for a major dam project in Mujohi area near Azad Jammu and Kashmir (AJK)'s capital city of Muzaffarabad.

A tunnel boring machine was engaged in excavation work when the explosion occurred killing three labourers on the spot and wounding 10 others. The wounded also included two Chinese engineers.

The victims, who hailed from nearby villages, were shifted to Combined Military Hospital (CMH) Muzaffarabad.

The cause of the explosion was not known but such incidents occur when boring machines strike a gas pocket while excavating.

Read: Neelum-Jhelum project may be further delayed, faces Rs50bn shortage

The 969MW Neelum-Jhelum Hydropower Project was scheduled to become operational by the end of 2016 but the deadline might not be met due to hostile contractors and other financial issues.

At least four people, including a Chinese engineer, were killed when a wall collapsed at the construction site in December 2014.

Also read: Chinese engineer among four killed in Neelum-Jhelum dam accident

—An earlier version of the story had reported the death of four labourers, the error is regretted