An internal investigation conducted by the police department led to the arrests of four city traffic agents yesterday on charges of handing out phony tickets in Manhattan, New York Police Department officials said.

The agents, who are not police officers, allegedly jotted down random license plate numbers and issued the fake tickets to drivers later in the day, the Manhattan district attorney’s office charged.

In some cases the accused agents — Davey Griffin, 30; Raheem King, 26; Julian Fisher, 24, and Gregory Baird, 56 — are alleged to have written tickets at times when investigators charged they were actually sitting down for lunch blocks away from where the ticket was issued, the head of the Internal Affairs Bureau, Chief Charles Campisi, said. He also charged that tickets were handed out to people on days they weren’t in New York City.

Mr. Campisi attributed laziness as the agents’ motive to hand out the false tickets.

Mr. Griffin, Mr. King, and Mr. Baird, who has been a traffic agent since 1978, are all being charged with multiple counts of forgery, which could land them in jail for up to seven years, the district attorney’s office said. Mr. Fisher faces six counts of official misconduct, a misdemeanor that carries a maximum sentence of one year in jail, officials said.

The agents in some instances preyed on vehicles with out of state license plates, which made it easier to falsify tickets on the agents’ handheld computers, Mr. Campisi said.

Most of the allegedly phony tickets were handed out in the Washington Heights and Inwood sections of Manhattan, the district attorney’s office said; Mr. Baird is also accused of allegedly handing out four false tickets while on foot patrol in Midtown.