HILLSBOROUGH (CBS SF) – The chief executive of a San Francisco-based tech company was arrested last week at his Hillsborough home on suspicion of oral copulation on a child, among other offenses, after police officers allegedly witnessed him sexually abusing his own son, prosecutors said Monday.

Zainali Jaffer, 29, was arrested at about 4 a.m. Oct. 15 at his home in the 1000 block of Lancaster Road.

Jaffer was the CEO and co-founder of mobile advertising firm Vungle. The company fired Jaffer less than a day after the arrest and replaced him with Chief Operating Officer Rick Tallman.

Police went to Jaffer’s home where they heard a child screaming and found Jaffer allegedly trying to force his three-year-old son’s face into his genitals, San Mateo County District Attorney Steve Wagstaffe said.

As officers tried to arrest Jaffer, he allegedly spat on them and resisted arrest.

Wagstaffe said police had to use a Taser to subdue Jaffer. Jaffer may have been under the influence of LSD, according to Wagstaffe.

Jaffer’s father initially called police and allegedly told them that his son punched him in the face.

Jaffer also allegedly punched his three-year-old and one-year-old sons, according to Wagstaffe. Both children suffered cuts and bruises but no fractures.

A post on the Vungle’s Facebook page by Tallman said, “We are aware of the extremely serious allegations leveled against our former CEO, and we are shocked beyond words. While these charges are completely unrelated to his former role at the company, they are obviously so serious that it led to his immediate removal.”

Tallman added, “The actions of one individual are in no way reflective of the almost 200 dedicated and hard-working people who work for Vungle. Everyone at the company is appalled and deeply saddened by these events.”

Jaffer is charged with five felonies and one misdemeanor. The charges include attempted oral copulation on a child younger than 10 years old, lewd act on a child by force, felony assault, felony child abuse, battery on a police officer and resisting arrest.

Jaffer’s attorney Daniel Olmos declined to comment.

Jaffer will appear next in court on Nov. 1, where he is expected to enter a plea, according to Wagstaffe.

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