SAN DIEGO -- A 36-year-old woman was in custody Thursday on suspicion of stealing more than $20,000 worth of valuables, some of them from an East County gym where she worked out, a sheriff's official reported.

At the time of her arrest on Wednesday, Tina Louise Waider of San Diego was allegedly in possession of a $1,600 stolen watch and someone else's purse containing items valued at more than $400, Sgt. Tom Poulin said.

Waider allegedly used a home-made device to open lockers at a 24-Hour Fitness Center in Santee, then stole items from them and stored them in her gym bag in her own locker at the health club, according to Poulin.

A subsequent search of Waider's Mira Mesa home turned up hundreds of other stolen items, including purses, jewelry, makeup, gift cards and expensive clothing with sales tags still attached, the sergeant said.

She was booked into the Las Colinas women's jail in Santee on suspicion of burglary, grand theft and possession of stolen property.