Tawana Johnson, 24, is accused of preying upon the elderly by first asking for help, then overpowering them.

Johnson was officially charged Wednesday with aggravated robbery in connection with one case that happened Dec. 26 at a North Side retirement community.

An arrest affidavit stated that a woman told police Johnson knocked on her door, asking her to use her phone so she could call her mother whom she said lived at the complex.

Police said once she was in the door, though, Johnson knocked the woman to the floor, kneeled on her and punched her.

The affidavit states that Johnson then took the woman’s purse and ran away, leaving her with a swollen eye. The woman had to be treated at a hospital, the affidavit states.

Robbery detectives with the San Antonio Police Department were already investigating several similar crimes and identified Johnson as their suspect in all of the cases, the affidavit states. A warrant was issued for her arrest on Dec. 28.

Police caught up with Johnson the following day. They said when they found her, she was driving in her car and had the woman’s wallet and other stolen items on the front seat, the affidavit stated.

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