Suspected militants gunned down an MLA, his young son and nine others on Tuesday in the deadliest ambush in Arunachal Pradesh, two days before the results of the Assembly polls are announced.

The four-car convoy of Tirong Aboh, the 56-year-old Khonsa West MLA who had been vocal against militants, ran into a hail of bullets in Tirap district around 11.30am. The militant outfit NSCN(K) is active in the area. No group has claimed responsibility so far.

Aboh, a resident of Dadam village in Khonsa who had won the Khonsa West Assembly seat in 2014 on a People’s Party of Arunachal (PPA) ticket, had been seeking re-election from the constituency as a National People’s Party (NPP) candidate.

Police said Aboh was returning from Assam to Khonsa, the headquarters of Tirap district, when armed men stopped the convoy near 12 Mile, about 20km from Khonsa, on Deomali Road and opened indiscriminate fire.

Of the 11 killed, nine have so far been identified. Besides MLA Aboh, those killed include his son Longgem Aboh, 20, personal security officers Ponhang Agi and B. Siksa, NPP state unit general secretary Wangngoi Hakhun, Jalin Hakhun, Ganwang Hakhun, Matlam Aboh and Pangro, a teacher. Two personal security officers of the MLA, Wangsan Hakhun and Wangdan Hakhun, are in hospital.

The army has launched a massive manhunt in the area.

Tuesday’s attack comes on the heels of the Centre partially withdrawing the Armed Forces (Special Powers) Act, which gives security forces sweeping powers, from three of Arunachal’s nine districts where it was in force.

Union home minister Rajnath Singh expressed “anguish” over the killings.