Police have opened a hate crime investigation after a group of Proud Boys threatened a Drag Queen Story Hour at a California library Saturday afternoon.

Five men shouted “homophobic and transphobic slurs at the event organizer” at the San Lorenzo Library, the Alameda County Sheriff’s Office said Sunday. The men were described as “extremely aggressive with a threatening violent demeanor causing people to fear for their safety.”

Children, parents and other community members were all in attendance at the story time.

Officials said responding deputies were able to “de-escalate” the situation before violence arose.

The investigation will look into “the annoying and harassing of children.”

“ACSO will dedicate all resources to ensure the safety of members of our LGBTQ community. We will make sure any future events at the library are safe against hate speech and threats of violence,” officials said in a statement.

“As we celebrate Pride Month, we will be swift in our response to any incidents where there are threats to harm members of this community.”

The Proud Boys have been designated a hate group by the Southern Poverty Law Center, which called them “one of a handful of far-right groups instrumental in instigating violence and civil unrest in the Pacific Northwest.” The group was designated a terrorist entity by the Canadian government in February for its members’ role in the Capitol insurrection and Enrique Tarrio, the former chairman, and four other members were indicted on Monday for seditious conspiracy for their roles in the attempted coup.

In Florida and Texas, conservatives have proposed banning children from drag shows; Florida Rep. Anthony Sabatini last week called them “perverted sex shows.” Florida Gov. Ron DeSantis was asked Wednesday about similar legislation and threatened child protective service investigations against parents who bring their children to family-friendly drag events.

“We have laws against child endangerment,” DeSantis told reporters.