New York, US: Three men were charged on Wednesday with conspiring to support Islamic State, including two who planned to travel to Syria to fight on behalf of the radical group, U.S. authorities said.

One of the men, Akhror Saidakhmetov, 19, of Kazakhstan, was arrested on Wednesday at John F. Kennedy International Airport in New York, where authorities said he was attempting to board a flight to Turkey on his way to Syria.

Another defendant, Abdurasul Hasanovich Juraboev, 24, of Uzbekistan, previously purchased a ticket for a March flight to Istanbul, said Loretta Lynch, US Attorney in Brooklyn.

Abror Habibov, 30, of Uzbekistan, was accused of funding Saidakhmetov's efforts.

All three men live in Brooklyn.

At a hearing in Brooklyn federal court for Juraboev and Saidakhmetov, Adam Perlmutter, a lawyer for Saidakhmetov, called his client ‘a very young man’ and said they would fight the case ‘vigorously.’

Habibov was expected to appear in federal court in Jacksonville, Florida, on Wednesday as well.

Juraboev drew the attention of federal agents when he posted messages on an Uzbek-language website stating his desire to join Islamic State and his willingness to kill US President Barack Obama. A US-led coalition has been fighting Islamic State, which controls swaths of Iraq and Syria.

Agents interviewed Juraboev at his home in August 2014, when he acknowledged wanting to fight for Islamic State in Syria and confirmed he would be willing to harm Obama, according to the criminal complaint.

He also told the agents about a friend, Saidakhmetov, who shared similar views, the complaint said.

Investigators recorded conversations between the two men using a confidential informant who approached Juraboev at a mosque, posing as a sympathiser.

The men discussed how to carry out attacks in the United States, according to the complaint.

‘I will just go a buy a machine gun, AK-47, go out and shoot all police,’ Saidakhmetov said during one conversation, the complaint said.

Saidakhmetov worked for Habibov, who operates mobile phone repair kiosks in malls in Florida, Georgia, Virginia and Pennsylvania, prosecutors said.

Habibov paid for Saidakhmetov's ticket and promised additional funds, according to the complaint.

A number of others have been charged recently with aiding Islamic State. At a speech in Washington earlier on Wednesday, FBI Director James Comey said Islamic State was using propaganda to attract ‘troubled souls.

Comey said there are Islamic State-related investigations into homegrown extremists in all 50 states.