Most of the victims were between the ages of 11 and 16, Radio Okapi said. They were suffocated during the mayhem Sunday in Butembo in eastern Congo's North Kivu province.
Radio Okapi said police tried to control the violence at Matokeo stadium by firing guns into the air to protect their commander, who was hit in the head and wounded by fans.
The two local clubs involved were Socozaki and Nyuki System, the radio said.
Dozens of teenagers marched through Butembo's dirt streets on Monday in protest and the regional governor paid a visit to the hospital.
North Kivu has been the epicenter of violence between Congo's army and rebels over the last year which has displaced hundreds of thousands of people.