RIVERSIDE (CBSLA.com/AP) — A Riverside lawmaker is backing new legislation that would change policies that shield some immigrants from deportation following the murder of a woman by an illegal immigrant on a pier on San Francisco’s waterfront.

45-year-old Francisco Sanchez pleaded not guilty Tuesday to first-degree murder in the death of 32-year-old Kathryn Steinle, who was shot and killed last Wednesday as she and her father took a walk on Pier 14.

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Sanchez, a repeat drug offender, was released from jail on April 15 in San Francisco.

Federal immigration authorities had filed a so-called detainer with San Francisco authorities, asking to be informed if they intended to release Sanchez.

However, the city’s sanctuary law prevents city workers from cooperating with federal authorities on immigration cases.

Jeff Stone, a Republican State Senator from Riverside, has authored new proposed legislation that would require any city or county in custody of a “felonious immigrant” to hold them for at least 48 hours to allow federal authorities to apprehend them.

Stone told KNX 1070 NEWSRADIO the legislation is not aimed at all illegal immigrants — just those who may pose a threat to public safety.

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“This is not going after nonviolent, non-criminal illegal immigrants, this is going after dangerous, felonious people that are in our states, that are being protected through these sanctuary cities,” said Stone.

Sanchez, a Mexican immigrant, appeared to confirm that he came to the city because of its status as a sanctuary in a jailhouse interview with a TV station.

A law enforcement official told the Associated Press Tuesday that a check of the gun’s serial number shows it belonged to a federal agent.

The official — who was not authorized to speak publicly about the case and spoke on condition of anonymity — declined to elaborate.

The San Francisco Police Department, which is investigating the case, refused to comment on the disclosure.

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