No people were injured in the incident.
Lt Jitthiwa Thanawitwilas of the Phuket City Police was informed of the incident at 2pm.
Investigators from Phuket City Police and from Phuket Provincial Police soon arrived at the scene ‒ a classroom on the fifth floor of a primary school building at a private school on Komaraphat Rd, in Talad Yai subdistrict in Phuket Town.
The Phuket Info Center did not name the school. Police have yet to issue any statement about the incident.
Prathom 5 students (about 10 years old) were taking art class in the room when the bullet came through the window, Phuket Info Center reported.
On realising what had happened, the art teacher quickly led the students out of the room.
Officers reported finding traces of gunpowder where the bullet passed through the window glass.
So far police have not confirmed finding the bullet.
Police are continuing their investigation and will check CCTV footage of inside the classroom at the time of the incident in the hope of learning more about what had happened, Phuket Info Center reported.