Two protesters were arrested at a controversial event inside the central branch of the Seattle Public Library on Saturday, while outside, hundreds of people held signs and chanted “trans is beautiful” and “bigots out.”

The event inside the downtown library was planned by a “radical feminist organization” called the Women’s Liberation Front (WoLF), whose views have been called anti-trans. Two attendees caused a disturbance during the event, according to Sgt. Sean Whitcomb, a spokesperson for the Seattle Police Department, and were asked to leave by library staff. When they didn’t,  Whitcomb said, officers arrested them and booked them for trespassing. At least one was carried out.

Meanwhile, outside, protesters who included library employees chanted, held signs and waved transgender pride flags. A band played and many danced to keep warm.

The planned event inside the library sparked controversy in recent months as transgender people and allies urged the library to cancel the event, which was publicized as “a critical analysis of gender identity” that would “make powerful arguments for sex-based women’s rights.” The Gender Justice League, one of the groups that organized the protest, said in a statement during the debate that the “end result of a hate group using the library as a venue to ‘critique’ the existence of a minority group creates a hostile environment and is unacceptable.” WoLF denies it engages in hate speech.

The union representing library workers also raised concerns about harm to library staff who are transgender.

The Seattle Public Library board decided last month the event would be allowed to proceed. The event was moved to a time when the downtown library is closed and increased security was planned, said Marcellus Turner, executive director and chief librarian.

Saturday’s protest began with a gathering and speakers at City Hall and then a march to the library.

This report includes information from The Seattle Times archives.