NEW YORK -- Two men were arrested Friday in the investigation of a suspected bomb plot targeting New York City, a case that has already led to charges against a Denver airport shuttle driver they attended high school with.

The arrests in New York of Adis Medunjanin and Zarein Ahmedzay were part of "an ongoing investigation" by the Joint Terrorism Task Force, according to FBI agent Richard Kolko, who declined to comment further.

There were no immediate details on the charges against the men, according to Kolko and Robert Nardoza, a spokesman for the U.S. attorney's office in Brooklyn.

The men were expected to appear in court later Friday, Nardoza said.

Medunjanin's attorney, Robert C. Gottlieb, said the FBI seized his client's passport Thursday. The search warrant indicated the passport was sought as part of an investigation into a conspiracy to use weapons of mass destruction, Gottlieb said.

The other suspect in the terrorism probe, Najibullah Zazi, previously pleaded not guilty to that charge.

Prosecutors accuse Zazi of traveling to an al-Qaida training camp in Pakistan in 2008, where he allegedly received bomb-making training and instructions. The FBI said it found a recipe for crafting homemade bombs from beauty product chemicals on the young Zazi's laptop computer.

Zazi and unidentified men are also accused of buying large quantities of the chemicals at Aurora beauty supply shops from July to September. Zazi was captured on store security cameras making the purchases, according to court records.

After Medunjanin's apartment was searched, he apparently became upset and left in his car. While driving erratically, he called 911 and made threatening comments, according to a law enforcement official who was not authorized to discuss the case and spoke to The Associated Press on condition of anonymity. Medunjanin got into an accident and was treated at a hospital for minor injuries.

Ahmedzay was arrested overnight while driving a cab in the Greenwich Village area of Manhattan, authorities said.

Federal investigators questioned Medunjanin and Ahmedzay -- who lived in the same Queens neighborhood as Zazi -- months ago in the terrorism probe. Their photographs were among four shown to Ahmad Wais Afzali, a Queens imam accused of tipping off Zazi that New York police detectives were looking for him, according to Afzali's attorney.

Gottlieb has said FBI agents seized computers and cell phones from Medunjanin's apartment last fall but later returned them.

Gottlieb said the FBI confirmed the arrests Friday morning, many hours after they occurred. He said he didn't know what charges the men faced.

Gottlieb insisted Medunjanin has done nothing wrong and said officials at the Queens hospital told him that authorities took him into custody after he was treated at the hospital.

"They intentionally hid him from his lawyer and his family," Gottlieb said.

The name of Ahmedzay's attorney was not on record.

Medunjanin, who is originally from Bosnia, and Ahmedzay, who was born in Afghanistan, are both U.S. citizens. They and Zazi attended Flushing High School in Queens.

Medunjanin also played football at Flushing High and graduated in June from Queens College. Ahmedzay is licensed to drive a taxi in New York City and took the civil service exam to become a firefighter, although his score made him unlikely to get an appointment.

Interviewed by the AP in the fall, Ahmedzay's brother, Nazir, denied that Ahmedzay had been involved in any plot against the U.S.

Ahmedzay and Medunjanin were first publicly linked to the investigation in September, when investigators raided their homes shortly before Zazi's arrest.

Authorities have been watching them for months. Gottlieb had previously confirmed that investigators had questioned Medunjanin and taken computers and cell phones from his apartment.

Prosecutors said that Zazi had recently traveled to a terrorist training camp in Pakistan, and that "others" -- who have been named -- accompanied him on the trip to the country.

A man who answered the phone at Ahmedzay's apartment Friday morning identifying himself as the suspect's father said he had just learned of the arrest.

"We saw it on the television this morning," he said. He said his son works the night shift, driving a cab, and didn't come home in the morning.

"I don't know what happened," he said. He said he didn't know whether his son knew Zazi or was involved in anything related to terrorism.