SAN FRANCISCO (AP) — A man who was severely injured in a fight after San Francisco's Bay to Breakers race last month has died, and police are again pleading with those who may have seen or recorded the confrontation.

Stephen Martin, 31, of Santa Clara, was taken off life support on Friday after being in a coma for three weeks.

"As per the doctor's recommendation, we took him off life support Friday morning — and allowed nature to take its course. Thank you all for your prayers and support," his family said in a statement.

On Monday, Police Chief Greg Suhr and top police brass pleaded publicly to those who might have taken photos or videos near the area of the May 20 attack to contact them.

"We can't get enough," Suhr said. "Err on the side of caution. If you think you have a photo or video that may be at all helpful, please send it along. ... Let us make the decision on whether it is useful or not."

Martin and his friends, wearing troll wigs, were standing in the Sharon Meadows area of Golden Gate Park hours after the race when a confrontation ensued with a group of 12 men and women — some wearing white and red San Francisco 49ers jerseys — over a cellphone, Cmdr. John Loftus said.

One man apparently wearing a Niners jersey punched Martin, Loftus said. Martin fell, struck his head on the park pavement and never regained consciousness.

Loftus showed photos of Martin and his friends posing with some of the alleged suspects before the altercation, including one man with a Niners jersey and a SF tattoo on the right side of his neck and a woman wearing an orange tutu.

Loftus said the suspects may be involved in a gang.

"We're trying to get photos of the actual assault," Loftus said. "We want to identify all of the people in this photograph. They are all people of interest."

Loftus added, "This is a tragic crime. This gentleman finished running the Bay to Breakers race several hours before and was socializing with this group, and now he's dead."

The 12-kilometer annual race from the city's Financial District to Golden Gate Park is infamous for its wild costumes, nudity and daylong revelry. In recent years, police have cracked down on runners drinking during the spectacle.

This year's race drew more than 40,000 participants, some of whom were dressed as penguins, superheroes and fruit. About 19 people were arrested that day.