Police are cracking down on unruly teens nationwide following the killing of a middle-aged woman, allegedly at the hands of five teenagers in Sa Kaeo's Aranyaprathet district earlier this month.

Police have been ordered to keep a close watch on teenagers aged 10-15 years who remain outdoors after 10pm.

In some provinces such as Nonthaburi and Samut Prakan, where incidents involving unruly youths often happen but also where there are not enough local police officers to deal with them, the Provincial Special Operation Sub-Division will also assist in the crackdown, the national police chief said.

Two police officers at the Aranyaprathet district police station are accused of torturing Panya Khongsaenkham into falsely confessing to killing his wife, Buaphan Tansu, known as Pa Kob.

She was killed by a group of teenagers aged 13 to 16, police said.

The teens, caught on a security camera attacking the victim, later admitted to killing Buaphan and disposing of her body in a pond on Jan 11. They are now being held in connection with her murder.

Police insisted that investigators were not trying to help their colleagues.

Police added that Mr Panya cannot testify as a witness because he is now being treated for alcoholism in a hospital.

Arrested shortly after his wife's body was found on Jan 12, Mr Panya allegedly confessed to the crime before footage from a security camera showed it was the five youths who were responsible.

Mr Panya said he was ordered to strip inside an air-conditioned room and told he could not leave the station until he had signed a written confession, according to deputy national police chief Pol Gen Surachate Hakparn.

A former director-general of the Department of Juvenile Observation and Protection on Monday suggested that a curfew be imposed to prevent teenagers from remaining outdoors for the sake of their own safety.

He said an 11pm curfew is imposed in Washington DC and other US cities such as New Orleans and Atlanta.