German police said Tuesday that a 15-year-old had been hospitalized with "life-threatening head wounds" after a brawl broke out during an international youth soccer tournament in Frankfurt.

Authorities later said that the youth had been declared brain dead by doctors, according to German media.

Frankfurt police said in a statement that the altercation started between players after the whistle had blown. The players eventually started throwing punches, resulting in the teen being struck by an opposing player.

What we know so far

The incident on Sunday occurred after a match between a youth team from Berlin and a French team.

A 16-year-old from the French team was jailed pending further investigation by a Frankfurt judge. 

The victim collapsed after he was struck in the head or neck area, police said. He was treated by emergency medical personnel at the scene before being taken to hospital.

Police are asking witnesses who may have video footage of the incident to come forward.

jsi/dj (dpa, AP)