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Arrest Made in Assault That Broke 70-Year-Old SF City Commissioner’s Arm

Written by Mike EgePublished Aug. 07, 2022 • 4:57pm
An SFPD vehicle is seen behind bars in the Mission Police Station in San Francisco, Calif. on Wednesday, May 25, 2022. | Camille Cohen/The Standard

San Francisco Police on Sunday arrested someone suspected of assaulting and breaking the arm of a 70-year-old city commissioner in SoMA last week.

The attack took place on the evening of Aug. 2 just a block from the home of the victim, Greg Chew, a former advertising executive who has served on the San Francisco Arts, Film and Immigrant Rights Commissions. 

Officials say the suspect knocked Chew to the ground and fractured his arm.

Five days later, at around 11:30 a.m. Sunday, officers assigned to SFPD’s Tenderloin Station spotted a man who matched the victim’s description of the suspect. Police say they found him at Eighth and Market streets and arrested him.

The suspect was identified as 34-year-old Derrick Yearby, of San Francisco.

Police booked him on charges of aggravated battery causing serious bodily injury, assault with force likely to produce great bodily injury, elder abuse and an enhancement for great bodily injury. 

Police still consider this case to be an open investigation despite the arrest. They urge anyone with more information to call the SFPD tip line at (415) 575-4445.

Mike Ege can be reached at

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