The incident, which was captured on surveillance camera, happened Sunday afternoon as the children were getting out of class at the mosque on Longwood Avenue.
Five-year-old Mohammed Ndiaye was with his cousin Yerime Dieye when out of nowhere, a man with a knife barged into the building and ran right into him, slashing him in the head.
"I would say to him, what was the point of running into a mosque when there's children around?" Yerime said.
Mohammed needed seven stitches to close that gash in his head, and with the help of his cousin, the soft-spoken first grader proudly revealed what he DIDN'T do at the hospital.
"They gave him Tylenol, and I don't know what you call it, so he wouldn't feel it," Yerime said.
"But I didn't cry," Mohammed said.
Police say it all started a few blocks away, where the suspect had just cut another man. As he fled the scene, authorities say he ran into the mosque. And as he reportedly stumbled through a curtain at the front door, he accidentally slashed Mohammed.
Yerime was there to help.
"As the man ran out, I looked at Mohammed's head," he said. "And he started screaming, and then was blood coming out of him. And the first thing I did was take my shirt off and put on his head and stop the bleeding."
Mohammed's mother Sokhna Sall was at home when it happened. She said she was very scared, nearly fainted and ran outside to see what was going on.
As for the suspect, he apparently stayed silent before fleeing.
"He said nothing," Yerime said. "Just ran in and ran out."
Anyone with information regarding the incident is urged to call police.