SAN ANTONIO – The U.S. Marshals Service has confirmed a person of interest in the death of San Antonio police Detective Benjamin Marconi is now in custody.

Chris Bozeman with the Marshal Service said the man was arrested around 8:30 p.m. The name of the man was not released. Bozeman could not confirm if the person detained was the same person San Antonio police was looking for.

Marconi, 50, was shot and killed during the morning while writing a traffic ticket outside Public Safety Headquarters.

Marconi was a 20-year veteran of the department and a father of two from Floresville.

"Most families will be celebrating the holidays. SAPD will be burying one of its own because of an ultimate act of cowardice, but a suspect who will be caught and brought to justice," police chief William McManus said at a news conference.”

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McManus said right before noon, the officer was writing a ticket in his patrol car when a black Toyota or Nissan pulled up behind it. A man got out the vehicle and shot the officer twice, once in the head. Marconi was taken to San Antonio Military Medical Center, where he died, McManus said.

The shooter was described as a black man around 5 feet 7 inches to 6 feet tall. He was wearing a gray shirt, black pants and has a goatee.