An 11-year-old boy has died after he was shot at a birthday party in Cleveland, according to police.

The mother of the 16-year-old host had allowed her son to host a birthday party but left to go to a nearby store when the shooting occurred Saturday around 9:30 p.m., according to a news release by the Cleveland Division of Police. It is unclear what led to the shooting.

Two juveniles carried the boy outside the apartment building on East 97th Street in Cleveland’s Hough neighborhood after he was shot in the chest to try and flag down help, police said.

The boy was later pronounced dead at the University Hospitals Rainbow Babies & Children’s Hospital.

The victim’s aunt told Cleveland.com that the family is “tired and hurt and frustrated.”

No arrests have been made, and the suspect is unknown, police said.