“I will try to discuss witness protection with local officials,” Angkhana Neelapaichit said on Friday.

She said her visit was prompted after she heard that a mentor of killed 17-year-old Chaiyapoom Pasae had found a bullet at the front of his house, which could be considered a warning, after he tried to defend the activist’s name.

Chaiyapoom was shot dead by a soldier on March 17 at a checkpoint in Chiang Mai’s Chiang Dao district.

Police and military officers have strongly suggested that Chaiyapoom might have been involved in the drug trade, while people close to the teenager disbelieve the accusations.

Police have labelled Chaiyapoom as a drug suspect after Third Army Area officers said a soldier shot Chaiyapoom in self-defence because he had pulled out a knife and then a hand grenade. Soldiers manning the checkpoint in Chiang Mai’s Chiang Dao district said they later found 2,800 methamphetamine tablets in Chaiyapoom’s car.