Authorities immediately launched a manhunt for the suspected gunman, later identified by Thailand’s Central Investigation Bureau (CIB) as a 34-year-old former policeman involved in an ongoing court case for allegedly selling drugs.

The suspect had appeared in court in Nong Bua Lamphu province hours before “opening fire while the kids were sleeping,” according to Maj. Gen. Jirapob Puridet of the CIB.

His two-year-old stepson was enrolled at the center he attacked Thursday, but was not present while the attack was carried out, according to a local police chief.

“[The shooter] went to look for his two-year-old son, but the boy was not there … so he started shooting as well as stabbing people at the nursery,” police spokesperson Maj. General Paisan Luesomboon told CNN.

Investigators later confirmed the suspect had killed his wife and his stepson before taking his own life. It is unclear if the gunman and his family are included in the current death toll.

The mass shooting took place at the Child Development Center in Nong Bua Lamphu province’s Uthaisawan Na Klang district, according to a statement from the prime minister’s office.

The province, located approximately 540 kilometers (around 335 miles) northeast of Bangkok, is a largely peaceful and quiet area, and is not known for violence.

“The prime minister has expressed his condolences on the shooting incident,” the statement read.