Thomas Daley, of Phoenixville, put cameras behind mirrors and in ceiling fans in bedrooms, bathrooms and living rooms at five apartment buildings in Norristown.

Prosecutors say it began in 1989 and continued until September 2008. Norristown police were tipped off when a tenant found one of the cameras.

Daley pleaded guilty in Montgomery County on Wednesday to more than 30 counts, including invasion of privacy.

The 46-year-old will be sentenced later. He faces 10 to 151 years in prison.

Defense attorney Tim Woodward says Daley never showed the videos to anyone else and "is extremely remorseful."