An Oakland man has been charged with four felonies after police say he assaulted then robbed a grandmother and one of her grandchildren on a walk in West Berkeley earlier this year.

And a red belt loop that fell off the man’s pants during the robbery ultimately led to his capture, authorities said Friday.

Officers from the U.S. Marshals Service picked up Kac Miller Jr., 19, earlier this week after Berkeley investigators put out the word that they were looking for him. According to court papers, when confronted by Berkeley investigators with the belt loop, Miller confessed to the crime.

The robbery took place back in late March, when a woman police described as elderly was walking with her three grandchildren, ages 2, 10 and 12, around Carleton and Acton streets at about 2 p.m.

A man came up to them and slammed the heads of the woman and her 12-year-old granddaughter together, according to court documents, then kicked them both while they were on the ground. He took the woman’s purse and the granddaughter’s bag, then fled.

Investigators pursued several leads but none initially panned out. They then turned their attention to a red belt loop found at the scene. One of the grandchildren told police it had fallen off the robber’s jeans, causing him to hold up his pants as he left the scene.

Police sent the belt loop to a lab for DNA testing, which led back to Miller when results came in earlier this month.

Marshals arrested Miller on Monday at his Oakland home and turned him over to BPD.

During questioning, police showed him a photograph of the recovered piece of clothing. According to court papers, “Miller recognized the photo of the red belt loop and confessed” to the robbery. “Miller stated that he needed money and was going through a hard time in his life.”

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The Alameda County district attorney’s office charged Miller on Thursday with robbery, elder abuse and two counts of child abuse.

According to charging documents, he was convicted as a juvenile for robbery in 2013, and sentenced to probation.

Miller also was arrested in Berkeley in June after authorities said he grabbed a purse and backpack from a woman who had bent down to tie her shoe while walking in North Berkeley. In January, he was arrested on suspicion of a home burglary in the 2500 block of McGee Avenue. The status of those cases was not immediately available prior to publication.

Miller remains in custody with a bail of $400,000, and is scheduled for a pretrial hearing Tuesday.

Police Lt. Ed Spiller said the case is a great example of the tenacious approach Berkeley investigators take to crime solving.

“We follow any leads that we have,” he said. “The victims were really traumatized by this. They were afraid to go out of their house after this, the kids and their grandmother. Investigators really wanted to find this person.”

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