Warriors head coach Steve Kerr feels the government needs to play a bigger role in preventing gun violence.

Ex-NFL player Jonathan Martin was detained at a Los Angeles-area hospital where he went to seek treatment Friday after his threatening Instagram post led to his former high school closing for the day, a person familiar with the situation told USA TODAY Sports.

Martin was trying to check himself into the hospital, according to the person who was not authorized to speak publicly.

“The individual we believe responsible for the social media post in question has been detained and our investigation is ongoing,” the Los Angeles Police Department said in a statement to USA TODAY Sports.

A private high school in a Los Angeles suburb was shut down Friday after threats posted to social media.

Students at Harvard-Westlake High in Studio City received an alert before school began stating the school was closed. Los Angeles police spokesperson Tony Kway told USA TODAY Sports that officers from the department’s North Hollywood division responded to the school “after an Instagram post by a former student who is now an adult.”

Kway said the department was unable to publicly confirm that Martin’s Instagram stories post was what caused the shutdown.

“When you’re a bully victim & a coward, your options are suicide or revenge,” Martin wrote in a photo posted to his verified Instagram account. He used the hashtags #HarvardWestlake and #Miami Dolphins.

Martin attended Harvard-Westlake before playing at Stanford and was drafted by the Miami Dolphins. In 2013, he accused then-Dolphins teammate Richie Incognito of bullying, leading to Incognito’s suspension.

Martin tagged Incognito and another former Dolphins teammate (Mike Poucey) in the post. He also tagged James Dunleavy, who attended Harvard-Westlake and was a walk-on basketball player at USC.

The shutdown of Harvard-Westlake comes a week after 17 people were killed in a mass shooting at Marjory Stoneman Douglas High in Parkland, Fla.

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