A Connecticut teen drowned during a swim class in his high school's pool last Wednesday, and was allegedly under water unnoticed for 17 minutes while other students swam around him.

According to reports, surveillance tapes showed Malvrick Donkor, 14, climbing down a ladder into the deep end, then sinking. The student went unnoticed until the class ended, when another student spotted his body underwater and told the teacher, who pulled him out. "There's no splashing, no flailing like you would typically think of," one source told the Hartford Courant. "He just slipped under water. Other kids were swimming over the top of him, not knowing he was down below." Donkor was taken to Manchester Memorial Hospital, where he was pronounced dead.

The swim teacher, Thayer Redman, has since been placed on administrative leave, and the pool has been closed. Manchester High Principal Matthew Geary says the situation is currently being investigated. "While many questions remain about this terrible tragedy, we have very little information to share at this time," Geary wrote in a letter posted on the school's website. "What happened on Wednesday was a terrible tragedy for Malvrick's family and friends, for those who were present during the emergency, for those who tried to provide help and support for Malvrick, and for the entire school community."

Geary led a prayer vigil for Donkor, a recent immigrant from Ghana, last night, which was reportedly attended by hundreds of students, parents, teachers and other community members.