By Leigh Martinez

STOCKTON (CBS13) – Authorities with the Department of Homeland Security and the FBI detained and released Stockton’s Mayor at San Francisco International Airport earlier this week.

Mayor Anthony Silva said he spent nine days in China recruiting Chinese businesses to San Joaquin County and Stockton. He posted his departure plane on his Facebook page September 19. When he returned to the US on Monday, he said he was detained at the San Francisco International Airport by the department of Homeland Security and the FBI

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In a statement Silva said, “DHS agents confiscated all my electronic devices including my personal cell phone.”

RELATED: Read Mayor Silva’s full statement on the detainment

Silva still has not received his electronics back.

“I am confident that any forensic search of my personal devices will never ever show illegal or inappropriate activities of any sort,” said Silva.

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When the FBI was asked if there is an ongoing criminal investigation of the mayor they said, “ I am unable to confirm or deny any of the claims and I have no information to release that may pertain to such.”

Silva said his host and sponsor for the trip was the Palo Alto non-profit “China Silicon Valley.” The organization’s website says its purpose is to promote investment and business communication between china and the Silicon Valley.

China Silicon Valley did not reply to our requests for information on the trip, however its website states the mayors paid $500 or more if they were VIP sponsors.

The city staffs of the mayors of Concord and Pleasant Hill confirm they were on the same China trip as Silva, but were not stopped or questioned at the airport.

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Silva said he has no idea why he was detained and why federal officials took his electronics.