BELMONT -- A 20-year-old Baskin Robbins employee pleaded not guilty Tuesday to selling drugs to two undercover cops while working behind the ice cream counter.

Martin Abinader, of San Carlos, was arrested April 8 on charges of marijuana sales and cocaine and hash possession after undercover detectives made two separate pot buys while he was scooping ice cream at a Baskin Robbins store. The officers wore wires as the Carlmont High graduate sold them the drugs at 1082 Alameda de las Pulgas, once from his black BMW and once in the store, packaged in a single-serve ice cream cup and Baskin Robbins bag, San Mateo County District Attorney Steve Wagstaffe said.

The six-week investigation began after someone told a school resource officer at Carlmont that Abinader was selling drugs to students out of the ice cream shop, Wagstaffe said. After doing their research on Abinader's methods, the two undercover officers were able to make two buys, one worth $50 and one worth $100.

"He didn't sell to just anybody -- you couldn't just walk in and say 'Hi, I want to buy drugs from you,' " Belmont police Capt. Pat Halleran said. "The investigators learned what they needed to say to get him to sell to them."

Police also found a small amount of cocaine and concentrated cannabis inside a cabinet belonging to Abinader, and he was handed an additional possession charge for each item, Wagstaffe said.

At the time of his arrest, Abinader's job description on Facebook read, "I run (expletive) at Baskin Robbins," but has since been changed to "Manager." Store owners could not immediately be reached to confirm whether or not he still works there.

While Abinader noted on the site that he has been working for the store since 2008, when he was 14, police investigators did not say how long they believed he had been running drug sales on the side. Investigators believe Abinader was alone in his actions at the ice cream shop, which is located in the immediate vicinity of several schools.

Abinader remains out of jail on $30,000 bond and will return to court July 2 for a preliminary hearing.

Follow Erin Ivie at Twitter.com/erin_ivie.