LOS ANGELES (CBSLA) — Authorities are asking for help in the kidnapping of a 28-year-old Chinese national from Orange County.

Ruochen “Tony” Liao of Santa Ana was last seen about 7:30 p.m. on July 16 at a shopping plaza in the 100 block of West Valley Boulevard in San Gabriel, where he may have been lured in connection with a business deal, according to the FBI.

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A sketch of one of the suspects in Liao’s kidnapping. (Image via FBI)

Three men of Chinese ethnicity were involved in the abduction, witnesses told authorities. They were riding in two very similar-looking, dark-color vehicles — a van, likely a Toyota Sienna or one similar to it, and an SUV, probably a Range Rover, according to the FBI.

Liao’s family is offering a reward of $150,000 for information leading to his return, while the FBI is offering a reward of up to $25,000 in the case.

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Ruochen “Tony” Liao of Santa Ana was last seen July 16.

Investigators say one suspect drove away with Liao in the van, and the other two suspects drove away in the SUV. A $2 million ransom was later demanded from the family, which was not paid, according to the FBI.

“Our hope is that Tony is still alive,” Gene Kowel of the FBI said during a news conference Monday morning at the Westwood Federal Building. “We’re operating under the premise that he is still alive, which is why this reward (and) this publicity is so crucial to the case. However, we do become concerned as these cases progress, the chance of someone remaining alive can diminish.”

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Anyone with information on the case was urged to call the FBI at (310) 477-6565.