DENVER (CBS4) – Two people were arrested Saturday afternoon while police monitored a group that had been staging protests throughout Denver.

During the protest a memorial dedicated to fallen police officers was vandalized, which has led to a controversy involving police administrators and the head of the police union, who is calling for Denver Police Chief Robert White to resign.

Approximately 100 to 200 people marched down Colfax Avenue from Lincoln Park to the Denver Police Department headquarters located at 1331 Cherokee Street. Some marched in support of Jessie Hernandez, a 17-year-old who was killed when she was shot by police during a criminal incident in January. While others demanded justice for people killed or “kidnapped” by police and protested “police terrorism.”

Denver police say some protesters poured red paint over the memorial dedicated to fallen police officers. The memorial is located in front of Denver police headquarters and lists the names of police officers who have died in the line of duty.

One protester told CBS4’s Lauren DiSpirito that he thought the protest was a success. Police say the vandalism was disrespectful. Some officers were seen with tears in their eyes after the memorial was defaced.

Police arrested two men for criminal mischief in relation to the vandalism. Denver firefighters were later seen cleaning the paint off of the memorial, but Denver Police Union President Nick Rogers said the damage had been done.

Rogers spoke exclusively to CBS4’s DiSpirito following the incident. He said officers monitoring the protest were told by their superiors to not to interfere and to let the vandalism happen. Rogers said he and officers are so upset about that decision that he’s calling for White’s resignation.

“There is no reason to allow someone to desecrate a memorial,” Rogers said. “There is no reason to allow that to happen, it’s wrong … we have a breaking point, and we are there.”

A police spokesman would not respond to the union president’s comments. Earlier in the day Cmdr. Matt Murray says its protocol not to engage protesters.

“We believe it’s better for the community not to have conflict,” Murray said.

Rogers said many officers take serious issue with the orders coming from the top.

“I will ask all 1,400 police officers to rally, and we will respond to the mayor’s office in unison to hand him a letter asking for the chief’s resignation,” he said.