More than a dozen people looking to buy heroin in Reading on Monday got more than they bargained for.

Members of the Berks County district attorney’s drug task force, the Reading Police Department’s vice unit and Pennsylvania State police served a warrant at 18 Mulberry St.

They went there upon learning that several street-level dealers were distributing packets of heroin from the home, officials said.

Over the course of the investigation in October, undercover detectives bought heroin worth between $30 and $60 from three different people at that home, officials said.

One of those people, identified by detectives as Rafael Machado-Machado, 42, of the 900 block of Court Street, was arrested Monday. He was charged with possession, possession with intent to deliver and delivery of heroin.

A second alleged dealer, identified as Melvin Ruiz-Caquias, was arrested Monday afternoon.

The third suspect, whose name has not been released, remains at large.

Detectives said they also seized from the home 12 packets of heroin, 13 packets of cocaine, numerous empty syringes and approximately $1,500 in cash.

After the warrant was served, undercover agents posed as drug dealers and sold purported packets of heroin to arriving customers.

The suspects arrested and charged with criminal attempt to possess heroin were identified by detectives as:

Carlos Rosario, 33, of Reading;

Francisco Perez, 54, of Reading;

Ernesto Serrano, 35, of Reading;

Israel Baez, 45, of Reading;

William Rodrigues, 39, of Reading;

Delano Bortz, 50 (no known address);

Jose Anibal Cruz, 31, of Reading;

Joseph Travis Curry, 31, of Mount Penn;

Robert Olley, 25 (no known address);

Julius Nathan Flynn, 62, of Reading;

Nancy Prince, 49, of Reading;

Jay Charles Reisinger, 52, of Reading;

Mark E. Gram, 47, of Reading;

Jose Luis Garcia Jr., 38, of Reading;

Jamie Serrano-Rosario, 46, of Birdsboro;

Edwin Ramos-Vega, 42, of Reading

Francisco Perez was also charged with aggravated assault on a police officer for biting a hand of an arresting detective, officials said. The detective did not require any medical treatment.