An East Palo Alto man who is charged with attempted murder after allegedly shooting at a vehicle on U.S. 101 faces 11 more felony charges.

Eric Valencia Vargas, 18, was in court Wednesday to enter a plea in connection with the Sept. 30 shooting at a vehicle on U.S. 101 in Belmont.

Police said they believe the motive for the shooting was a rivalry between two gangs in East Palo Alto and Menlo Park. Video-surveillance cameras captured Mr. Vargas following the victims' vehicle from the entrance of the San Mateo Bridge. Two people were struck by the gunfire and taken to the hospital. Both recovered from their injuries, prosecutors said.

In addition to the 11 new counts, he appeared in court Wednesday on these charges: three counts of attempted murder; three counts of using a weapon of mass destruction (using ammunition designed to penetrate metal or armor); three counts of using a firearm to cause great bodily harm; three counts of being a gang member and firing upon an inhabited vehicle; two counts of committing crimes while being in a gang; three counts of resisting arrest and multiple other weapons charges.

On Nov. 14, members of the San Mateo County Gang Task Force contacted Mr. Vargas in East Palo Alto. They found that he was in possession of a loaded Glock handgun with an extended magazine and attempted to place him under arrest. Mr. Vargas fought with several officers before being subdued and taken into custody, prosecutors said.

Forensic analysis linked the Glock firearm to the shooting, the DA's office said.

Mr. Vargas was to enter a plea on Wednesday, but that has been postponed. The new charges include 10 felony counts of threatening a police officer and one count of felony gang conduct. Mr. Vargas is scheduled to return to court Jan. 22 to enter a plea and to set a preliminary hearing date. He remains in custody on no-bail status.

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