Shen Ji, 25, was charged with rape and robbery by Minhang District prosecutors.

Shen was hired to be a security guard at Fanlin Garden residential community last June but he wasn't satisfied with the 1,000 yuan (US$124) monthly income, prosecutors said.

He paid special attention to "wealthy families" in the community and often talked with residents to learn about their situation. He resigned in October, prosecutors said.

On March 25 this year, Shen visited the community and spoke to another security guard. He saw a Hyundai being parked and remembered the owner was a young woman surnamed Chen who lived alone.

Prosecutors said that was how Shen chose his victim.

Shen then left, making sure the security guard witnessed his departure. Later that day, he returned in a taxi, knowing that guards don't check passengers in cabs. The suspect then opened the security door using the old code and entered Chen's building, prosecutors said.

He told the woman he was there to check the alarm. Since Chen recognized him and didn't know he resigned, she let him in without question.

After he was sure Chen was alone, he allegedly tied her up and stole 1,000 yuan, a mobile phone, a digital camera and three bank cards.

After forcing Chen to give the passwords for the bank cards, the suspect allegedly raped her and took photos of her while she was naked. He used the stolen camera.

He allegedly threatened to e-mail the photos to Chen's company if she reported to police.

Shen then left the building and climbed over a wall to escape. He withdrew 54,000 yuan with the bank cards, prosecutors said.

Chen reported to the police after she freed herself.

Police officers caught Shen in Hangzhou, the capital city of Zhejiang Province, five days later.

By Xu Fang