Police have arrested a 53-year-old Anoka County man on suspicion of secretly shooting videos of children undressing at area YMCAs.

Although the number of possible victims isn't known, investigators are searching at least 150 suspected files on the man's computer, said Cmdr. Paul Sommer of the Anoka County Sherrif's Office.

"We anticipate many victims, although they are most likely unaware they have been victimized," he said.

The man, who hasn't been charged, was arrested Feb. 24 after a 12-year-old boy reported to his parents that a man was holding a watch over a partition where he was getting dressed at the YMCA in Andover. The incident was reported to staff and the sheriff's office.

Using video surveillance from inside the health club, the man was identified by the boy, said Sommer.

A search warrant was executed Saturday at the suspect's home in Coon Rapids, where he lives with his parents, authorities said. During the search, a wrist watch that had digital video and still photo capability was found near a computer. A second search warrant was executed for data contained on the computer. Preliminary results showed numerous files that depict boys in various states of undress at the Andover and Coon Rapids YMCAs and at least one other as-yet-unknown athletic facility, said Sommer.

There was also child pornography found on the computer that police don't believe was produced by the suspect.

Charges are expected to be filed Tuesday.

David Chanen