A chase involving two men led into the Derby Public Library on Monday.
Police said they're trying to figure out the identities of the two men who were involved.
The incident was caught on the library's surveillance cameras.
Police said around 12:30 p.m., a male suspect was chased by another male from Seymour Avenue into the Library on Elizabeth Street.
The chase continued through the library, after which the suspect fled onto Caroline Street and into a white car that was waiting on Seymour Avenue.
"We're looking to identify, not just the who, but the what and the why of the video," said Lt. Justin Stanko from the Derby Police Department.
The video has been viewed thousands of times on the Derby Police Department's Facebook page.
"I've never seen something like that and it's very scary because I come here all the time by myself," said Carolyn St. Pierre of Seymour.
Police said they've had several tips already, not just from people, but from other police departments, identifying the two men.
"We have every reason to believe they're from the valley, Ansonia, Derby, our crimes kind of co-mingle, so we're working together on it," said Stanko.
The big question is what's going on and more specifically, what's behind the chase, which is clearly something serious.
"It's our job to figure out what led up to it, what happened during it, and more importantly is there anything that's going to come after it," said Stanko.
Anyone with information is asked to contact detectives at the Derby Police Department. Their phone number is 203-735-7811.
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