SANTA MONICA – Video of a Santa Monica High School student being subdued by a wrestling coach, supposedly after selling marijuana in his classroom, is becoming a worldwide web sensation, but has triggered a backlash from parents, teachers, students and alumni.

School officials said Mark Black was put on leave pending an investigation.

The teacher’s boss sent a letter home Friday stating “a number of videos capturing at least a portion of the incident are circulating, and I can tell you that what I witnessed on one of those videos is utterly alarming.”

Based on what she has seen, the “physical restraint” used by the teacher was “unacceptable,” wrote Sandra Lyon, superintendent of the Santa Monica Malibu Unified School District.

That infuriated many in Santa Monica, and a Facebook page supporting “Coach Black” passed 2,500 members in a half day.

The incident, according to student witnesses who spoke to TV stations, started when the teacher tried to confiscate a bag of cannabis and was set upon by the teenager. Black was reportedly stabbed by the student with a pencil.

No punches were thrown, and Black eventually can be seen with his arms locked around the student’s legs, on the floor.

Witnesses told TV stations the student was arrested, but the teacher was not. A Santa Monica police spokesman declined to comment on the incident and instead referred questions to the school district.

And answers from SMMUSD to those questions angered many. Lyons, in her letter to parents, wrote “we have been in contact with the student’s family, and we will work with them to offer the support that they may need.

“I am grateful that there is no reported serious physical harm to students or teachers, but that neither dismisses the severity of this situation nor my commitment to gather all the facts and make sure the proper actions are taken,” Lyon wrote.

That infuriated many teachers and parents. On Facebook, they rallied around “Coach Black.”

“Terrible job by the superintendent making statements without full knowledge of the situation … poor leadership and not very supportive of her teachers,” wrote John S. Dahlem, who identified himself as a teacher in Orange County who grew up in Santa Monica.

“The superintendent needs to read the Education Code on reasonable restraint and the rights of teachers to defend themselves when being attacked, stabbed with a pencil, etc.”