Haflong (Assam), May 15: Striking in a big way, Dimaa Halam Daogah (Jewel) militants killed at least 12 people, including two NF Railway employees, in Assam's North Cachar Hills district on Thursday, where all trains were cancelled. The DHD militants also known as `Black Widow' gunned down 10 persons - drivers and helpers - of five cement laden trucks at Untriskilo, official sources said.

The ultras also set ablaze the trucks, the sources said.

The driver of a special train patrolling between Lumding and Haflong for security checking of tracks noticed fish plates missing in between Mopa and Kalajan railway station at around 7.30 am.

He stopped the train and got down along with his gangman to see the tracks when the DHD ultras gunned them down and injured the assistant locopilot, the sources said.

The driver was identified as N N Bora, gangman as R Thakuria and assistant locopilot P K Deb, the sources said.

The N F Railway has cancelled all trains in the district between Badarpur and Lumding following increased attack on its employees and labourers engaged in broadgauge conversion work.

The district had observed a 24-hour bandh on Wednesday to protest the killing of 13 labourers engaged in broad guage conversion work and East-West Corridor highway construction since Saturday by the militants.

The militants had also killed a railway employee and two others at Maibongdisa railway station in the district.