Police are investigating thefts from employees at Boston City Hall.

Several workers told Boston police that hundreds of dollars in cash, debit and credit cards were stolen, among other items, between 11 a.m. and 1 p.m. Monday, according to a police report. Unauthorized charges totaling hundreds more dollars were also made at Macy’s and Walgreens.

“Boston City Hall must be a safe and welcoming space all year round for residents, visitors and our City employees,” a city spokesperson said in a statement to NBC10 Boston. “Boston Police are investigating this incident to ensure that any needed security protocols or resources will be addressed.”

Victims reported having seen an unknown man wearing a blue face mask, sweatpants, a dark jacket and a brown beanie.

“I was there on Monday and I was there on Tuesday, and it was very quiet,” Boston City Councilor Ed Flynn told NBC10 Boston. “Apparently, there was a person walking from office to office, and had the free rein of the building for a period of time.”

Flynn said he is concerned by the possibility of confidential information being taken.

“There could have been information about taxes, there could have been someone’s Social Security number, mortgage documents or car-related information,” he said.

He’s calling for tighter security after the incident.

“We can’t sweep this under the rug as if it’s only a minor incident of theft,” Flynn said. “It’s more than that.”