A teacher at a private junior high school is facing disciplinary action over Facebook postings that included a photo of him punishing students accompanied by humiliating comments, school insiders said Monday.

The homeroom teacher of a first-year class at Kobe Ryukoku Junior High School, operated by a body that also runs a high school, was suspended from work Monday pending a formal decision on final disciplinary action, the sources said.

According to the sources, during a study camp of first-year students held July 17 to 19 on the coast near Toyooka, Hyogo Prefecture, the teacher, who also acted as a guidance counselor, uploaded photos of two first-year students forced to sit on the floor in the "seiza" position, resting their buttocks on the heels of their folded legs.

Forcing students to sit in that position for an extended period was once a typical way for teachers to discipline students, although the punishment is no longer common.

Besides making the humiliating photo public, the teacher wrote: "I forced them to play in a play area in the lobby (of the camp facility) for young children for 30 minutes."

"I made them cry in front of their parents before we parted" after finishing the camp, read another comment.

The sources said the teacher, whose name has been withheld, explained he "only wanted to educate them and was being strict, but I think I went too far."

"It's such a shameful act for a teacher, and I take it gravely because I regard it as physical punishment," said Harufumi Hirota, vice principal of the affiliated high school. "We are planning to set up a third-party committee to discuss measures to prevent recurrence of such incidents in the future."