A South Korean accused of spying on North Korea for his government for at least the last five years has been charged with repeatedly lying about his activities in America, federal authorities said yesterday.

Park Woo, also known as Steve Park, who has lived in America for 20 years, was arrested Wednesday and charged in U.S. District Court in Manhattan with lying to the FBI about his role as a South Korean agent.

At a court appearance yesterday, the chief of terrorism and national security for the U.S. attorney’s office, Edward O’Callaghan, asked that Mr. Park be held without bail. Labeling Mr. Park a risk to flee and a danger to the community, Mr. O’Callaghan said espionage charges were likely.

Mr. Park’s lawyer, Deirdre Von Dornum, said her client, living in America with his wife and daughter, both American citizens, was unlikely to flee because he had spoken to FBI agents once in 2005 and twice this year and never fled even though he had traveled heavily.

Saying her client had been law abiding for 20 years, Ms. Von Dornum predicted that the case would turn into an instance in which “what appears to be quite bad turns out to be much less.” She said the charges her client currently faces would result at worst after a conviction in a sentence of one to two years in prison.

U.S. Magistrate Judge Ronald Ellis said Mr. Park, 58, could be freed on $150,000 bail. He ordered electronic monitoring as well. American laws require anyone acting as an agent of a foreign government to register with the attorney general and disclose the nature of the activity. An FBI agent said in court papers that Mr. Park had not registered.

Mr. O’Callaghan said federal agents found $2,000 cash in Mr. Park’s Manhattan apartment and Mr. Park admitted to them that he had received cash payments over the course of several years that appeared to be his only income.