NEWARK — Dave Herman, a pioneering New York City radio personality who was in jail facing charges related to a child sex sting operation, died on Thursday. He was 78.

Mr. Herman died at University Hospital in Newark, his lawyer, Marc Agnifilo, said. He had been rushed to the hospital late on Wednesday from the county jail after complaining of chest pains, Mr. Agnifilo said. No official cause of death was announced.

Mr. Herman had been living in St. Croix, in the United States Virgin Islands, and was arrested at the airport there in October on a charge that he had tried to transport a 7-year-old girl to the territory for sex. He was said to be communicating with someone who he believed to be the child’s 36-year-old mother in his efforts to arrange a sexual encounter with the girl. He was believed to be waiting to meet the pair.

Mr. Herman pleaded not guilty to the federal charge, but was denied bail. Mr. Agnifilo had suggested that Mr. Herman was duped by an undercover police officer.