Twenty-nine people were arrested for participating in a Black Lives Matter protest that caused major traffic delays on I-93 north and south of Boston on Thursday. One of the demonstrators worked for the City of Boston and was fired by Mayor Marty Walsh.

According to the Boston Herald, Nelli Ruotsalainen, who was arrested for participating in the Milton protest (the other taking place in Medford), worked part-time as a youth communication specialist for the Boston Centers for Youth and Families.

The Norfolk District Attorney’s Office stated that Routsalainen, 25, of Lambert Avenue, Roxbury, pled not guilty to trespassing, throwing glass on a public way, willfully obstructing an emergency vehicle, conspiracy, disorderly conduct, resisting arrest and throwing an object on a public way.

“As mayor, you have to make tough, difficult decisions. This is not a difficult decision,” Mayor Walsh told The Herald. “This was not based on the fact of this woman protesting. It was based on the fact of putting the public safety of other people at risk.”

Massachusetts State Police Colonel Tim Alben told reporters in a press conference that the Easton Fire Department responded to a car crash where the victims sustained life-threatening injuries. They were on their way to a Level-1 trauma center in Boston but because of the delays caused by the protesters, had to divert themselves to a Brockton hospital.

Boston Police Commissioner Bill Evans is reportedly just as frustrated with the demonstration as Colonel Alben.

“If lives mattered today, those kids wouldn’t have been out there doing what they did because they put a lot of lives in danger,” said Commissioner Evans according to WCVB. “This isn’t a normal group that’s been operating in the city. This was again an Occupy anarchist movement who was hell-bent on causing problems and they used it in the name of Black Lives Matter.”