A student was stabbed by a classmate during a fight Thursday morning inside a Boston middle school. The incident happened at 9:26 a.m. at the Washington Irving Middle School on Cummins Highway, police said. The victim, a 13-year-old boy, is in the hospital with minor injuries. The 14-year-old accused in the attack is in police custody. Students said the teens had an argument outside of the school after class on Wednesday. The more than 500 students were put in lock down after the incident. St. Lucie Public Schools has not responded to requests for comment.