Police have pressed an additional charge of drug abuse against an officer who opened fire in a Bangkok police station on Wednesday.
Pol Lt-Colonel Burin Lalitathada is now in detention and has been dismissed from the service.
"Evidence has suggested that his behaviour had something to do with methamphetamine consumption," Metropolitan Police Division 5 chief Maj-General Suebsak Phansura said yesterday.
He said Burin was also found to have previously sought drug rehabilitation from the Thanyarak Institute.
"There have also been reports of him firing shots from his gun elsewhere as well,' Suebsak said.
Burin was arrested in a border province on Thursday for allegedly firing several rounds from an M16 machine gun inside Khlong Tan Police Station in Bangkok. At the time of the shooting, Burin was serving as an inspector at another station in Bangkok.
Metropolitan Police Commissioner Camronwit Toopgrajank said yesterday that Burin would also face a strict disciplinary probe.
Suebsak said the M16 machine gun used by Burin was not an authorised weapon and that he had acquired it on his own.
However, the handcuffed former police officer denied ever owning the M16 assault weapon, claiming it was a "set up".
He denied he was planning to flee the country when asked what he was doing at the Myanmar border, saying: "I only wanted to visit a temple there."