Hundreds of transgender pride flags were removed from a memorial set up on Boston Common this week and it's unclear who was behind it.

More than 400 flags were installed by the Queer Neighborhood Council last Sunday to honor transgender people who had been killed in recent years. November is Transgender Awareness Month and the 20th was an International Day of Remembrance.

"We've been organizing for a few months now and we raised funds to buy these flags," said Jack Imbergamo, the executive director of the council.

Imbergamo told WBZ-TV he got a permit from the city to install the flags. On Monday, someone sent him an an email stating they saw the flags being pulled out of the ground. 

"We had talked about that being a possibility, but I don't think it could have prepared me for it," Imbergamo said. "I wasn't prepared to be as upset as I was."

There are no leads as to who vandalized the memorial. Imbergamo said he filed a report with Boston Police, but a BPD spokesperson told WBZ on Thursday they were "unable to find a police report at this time." Advocates pledged to reinstall the memorial on the Common next November.

"We're just going to move forward. We're just going to keep going, put one foot in front of the other," he told WBZ.

On Friday, the city said it is working with the organizers to ensure the memorial has a new protected home. The display will be placed at the Rita Hester Community Garden in Allston. 

In a statement, a city spokesperson said: "Boston stands with our trans neighbors and firmly against all hate, discrimination or violence. Our residents should feel safe and supported in every neighborhood across the City. No act of prejudice is tolerated here - we will continue to work with BPD to assess the situation and identify those who are responsible." 

On Thursday, a vigil was held at the Isabella Stewart Gardner Museum where nearly 300 names were read. Each was a transgender person who had died violently around the world this year. The vandalism to the installation was top of mind for people in attendance. 

"Right now, the world feels somewhat of a scary place for trans and gender expansive folks," said Mason Dunn, the executive director of Planned Parenthood Advocacy Fund of Massachusetts. "I think it's most important that we come together in community and that we find strength and solidarity in our community in times like these." 

"We should be remembering these names not just today, but that we should carry with us every day, the fact that transgender people are here, deserve to be heard, are resilient," Dunn said.