A Merced resident responding to a Craigslist ad to buy a vehicle was robbed at gunpoint Wednesday night by the people who posted the ad, Ceres police reported Friday. The victim was uninjured, but his wallet, cash and stereo equipment were taken.

The suspects' vehicle was at Service and Mitchell roads Thursday when a felony traffic stop was conducted. It was occupied by Jesus Diaz Jr., 32, of Ceres. A second vehicle determined to be related to the case was stopped in the area. The driver, 19-year-old Noah De La Rosa of Modesto, was in possession of ecstasy pills, police said. He and Diaz were detained.

A search warrant executed at Diaz's residence in the 2500 block of Lynell Avenue in Ceres turned up the guns described by the victim: a Mac-10 assault weapon and a .380- caliber handgun, along with more than a pound of marijuana and the victim's stereo equipment, identification and Social Security card, said Ceres police spokeswoman Carissa Higginbotham.

Diaz was arrested and booked at the Stanislaus County Jail on suspicion of conspiracy, robbery, being a felon with a prior weapons offense in possession of a firearm, possession of an assault weapon and vehicle code violations. De La Rosa was arrested and booked on suspicion of robbery, conspiracy, possession of ecstasy and possession of an assault weapon.

Anyone with information on this case should contact Detective Derek Perry at (209) 538-5730, or tips can be anonymously reported to the Stanislaus Area Crime Stoppers at (866) 602-7463. Tipsters can text information to Crime Stoppers by sending a text message to 274637. Type "TIP704" plus a message.