MADISON, Wis. -

A 19-year-old man was knocked unconscious Friday night after a dispute on West Lakelawn Place, police said.

Witnesses said there were several young men outside and they heard a lot of shouting and someone yell, “If you ever go near her again, I will kill you,” according to a release.

One of the men punched the 19-year-old in the head, which caused him to collapse, police said.

The 19-year-old was taken to a hospital with a concussion and a black eye, according to the release. The attacker has not yet been identified.