Police have arrested a suspect in the murder-robbery of a gold shop in Lop Buri two weeks ago, in which a young child and two adults were killed in cold blood.
The suspect is the director of a school in neighbouring Sing Buri province, according to media reports.
Deputy Prime Minister Prawit Wongsuwon said on Wednesday morning the man had confessed, and said he acted alone.
The suspect is accused of the gold robbery at Robinson Department store in Muang district of Lop Buri on Jan 9, when the robber callously shot dead three people - including a two-year-old boy - and wounded four others.
National police chief Pol Gen Chakthip Chaijinda confirmed to reporters at the tourist police office in Lop Buri on Wednesday afternoon that a suspect was arrested and was being interrogated. The suspect was definitely not a scapegoat, he said.
Further details would be given on Thursday morning, he said.
Although people were angry about the crime, they should not consider taking violent action against the suspect, who had already entered the justice system, Pol Gen Chakthip said.
The police chief said he had asked the suspect why he did it, and he had answered. He refused to elaborate.
"The suspect was cooperative. He said he knew well he could not escape. He did not resist arrest," Pol Gen Chakthip said.
Media reported that the suspect was the newly appointed director of a school with about 40 kindergarteners and primary pupils in Sing Buri province, not far from the crime scene in Lop Buri, and a gun enthusiast.
The 38-year-old man had a master's degree was married three years ago, and showed no signs of violence around his colleagues.
The cruel murder and robbery happened at Aurora gold shop inside Robinson shopping mall on Phahon Yothin Highway in tambon Kok Ko of Lop Buri's Muang district at 8.44pm on Jan 9.
Surveillance camera footage showed the robber used a pistol fitted with a long sound suppressor to quickly and skillfully shoot customers and gold shop staff as he walked up to the store in the mall area.
He also fired without hesitation at a two-year-old boy who was walking past the shop with his mother. The robber shot dead a security guard as he left, fleeing on a motorcycle with gold worth about 500,000 baht.