SAN FRANCISCO (KPIX 5) — Police in San Francisco on Friday were asking for the public’s help to locate a computer programmer who has been missing for more than a month.

The man’s family is worried his disappearance could involve foul play.

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Family members told KPIX 5 the last known location of 50-year-old San Francisco resident Chris Woitel was his Mission District apartment.

Christopher Woitel of San Francisco was last heard from on January 9, 2021. (San Francisco Police Department)

Christopher Woitel of San Francisco was last heard from on January 9, 2021. (San Francisco Police Department)

Surveillance video taken from the apartment building showed Woitel entering his building and walking to his apartment with a bottle of wine on January 8th. His family members said they talked to him on January 9th.

Woitel is also known to frequent the Emeryville area and the town of Sonora in the Sierra Foothills.

Since then, they say they have received no communication from him and seen no video of him walking out of the building.

“There’s been no activity. He’s not been in his apartment. There’s no activity on his bank [account]. We’re very anxious to find him,” said Woitel’s older sister Lara Haben.

Woitel’s two sisters and a brother flew to San Francisco from Chicago to help with the search. They passed out missing person flyers near his building on Friday afternoon at the corner of Guerrero Street and Duboce Avenue.

The siblings said it is out of character for the computer programmer to disappear.

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“It’s been horrible. It’s hard to sleep. It’s hard to think. It’s hard to focus on anything else. We miss him so much,” said Kathy Flynn, Woitel’s other older sister.

“There isn’t a day goes by at this point without wondering, ‘What happened? Where is he?,'” asked older brother Frank Woitel.

The family filed a missing person report with San Francisco police on January 13th. They also hired a private investigator who concluded an acquaintance of Chris Woitel was involved in the disappearance.

Police have been tight-lipped about the case. Authorities told KPIX they were actively investigating Woitel’s disappearance, but wouldn’t say if they have interviewed anyone or developed a person of interest.

“Fearful that something could’ve happened,” said Flynn.

The family said Woitel is 50 years old, 5’10” tall and weighs about 200 pounds. They said they were prepared for the worst and hoping for the best.

“We want him to come home. We just need him to come home,” said Haben.

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The family will continue to pass out flyers and try to generate more leads this weekend. They fly back to Chicago on Sunday.