SAN DIEGO -- At least one of the suspects accused of robbing and shooting an 18-year-old man responding to a Craigslist ad may have been behind a similar crime just a week prior, according to San Diego police.

Police believe the three teenagers linked to the fatal shooting of Garrett Berki are part of a gang that, on several occasions, targeted San Diegans looking for Craigslist bargains.

According to police, the most recent fake transaction ended in Berki's death. Police said Berki thought he was buying a computer when he met the suspects in Paradise Hills.

10News obtained a search warrant that revealed Rashon Abernathy may have been behind at least one other fake Craigslist ad a week before Berki's death. The ad advertised a Macbook Pro for $900.

Police said the robbery happened on May 5 at the Paradise Hills Community Park, and they believe Abernathy and a fellow gang member met with another victim. Police said that victim was robbed of $600.

According to police, the victim chased them out of the park, but when one suspect -- believed to be Abernathy -- pointed a gun at him, and the victim ran back to his car and called authorities.

The next day, police went to Morse High School and took Abernathy's acquaintance into custody.

Police said that same suspect is accused of a similar robbery committed just three days prior.

In that robbery, police said a fake ad listed diamond earrings for $4,000 or best offer. The victim met two suspects along 7400 Ledgewood Place in the Bay Terraces area.

According to police, the victim agreed to drive to his bank to withdraw money with the suspects in his car. They returned to the location, and that’s when police said one suspect starting punching the victim in his face demanding his money and keys.

A second suspect sprayed the victim's face with an unknown chemical, police said. The victim managed to get out of the car, but the suspects continued to beat him on the street, grabbed his $1,600 in cash, his keys and took off in his car.

A witness across the street called the victim to her house and called police. That victim was treated and released for non-life threatening injuries.

Police said gang members will commit robberies to bolster their reputation within the gang. They use the money they steal to buy weapons to be used in other crimes, police said.

10News reached out to Craigslist officials for a comment, but have not received a response.