As a shopper fit her baby into a car seat Wednesday evening, a man pedaling by on a bicycle stopped and asked the time.
Seconds later, he came back with his left hand poked against the inside of his shirt.
"Ma'am, I'm going to rob you," the man told the woman in the parking lot of Best Buy on U.S. 19 and Drew Street.
He demanded the woman's purse, then took off on his bike.
The woman called police. Then she called and canceled her credit cards, a move police said was very wise.
"She had the wherewithal to report it as stolen," police spokesman Wayne Shelor said.
An hour after the robbery, at a nearby Target store, a man loaded a shopping cart with $900 in electronics merchandise, including a DVD player, a PlayStation 2 and a portable phone.
He tried to buy the items with a credit card, but the cards had been red-flagged as stolen, police said.
Store workers called police. Back in the Best Buy parking lot, Officer Angela Wannos heard the call on her radio.
The description workers provided dispatchers matched the description of the man who committed the robbery.
Officers went to the Target store, where they found a man with the woman's credit cards and cell phone.
Police arrested Anthony E. Lawson, 27, of Oldsmar, on charges of strong-arm robbery and fraudulent use of a credit card.
He also was charged with grand theft on a warrant out of Broward County. He admitted to the crimes, Shelor said.
Lawson was being held without bail Thursday at the Pinellas County Jail.
Police said the incident is a valuable reminder that canceling credit cards immediately after a theft can pay off.
"It kept her from getting false charges," Shelor said. "It's specifically what led to his capture."