A fourth suspect in the alleged plot to attack New York's John F. Kennedy International Airport, who is still at large, is considered "armed and dangerous," the police commissioner in Port of Spain, Trinidad, said Monday.

A photograph of Abdel Nur — a Guyanese man described as 176 centimeters tall with black and gray hair and brown eyes — was distributed after the news conference, held by Police Commissioner Trevor Paul.

"The offense is indeed a serious one," Paul said. "We will not allow anyone to cause disruptions to our country ... This is our country, and we need to protect it from possible attacks."

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Also on Monday, the leader of a radical Trinidadian Muslim group denied that his organization had any connection to the four men accused of planning to attack JFK Airport.

Yasin Abu Bakr, the leader of Jamaat al Muslimeen, told The Associated Press he knew "nothing" about the alleged plan to bomb a fuel pipeline feeding the airport, a plot authorities say was hatched by a group that included a former Guyanese politician.

U.S. authorities claim the alleged plotters sought support in Trinidad from Jamaat al Muslimeen, which staged a deadly coup attempt in the Caribbean nation in 1990. The men did not receive such support, according to court documents.

But the documents also say that Nur, thought to be still at large in Trinidad, said he met in May with Abu Bakr at his compound in Trinidad and the Islamic leader suggested that he return later with others involved "to discuss the plan in detail."

Nur allegedly said the Jamaat al Muslimeen leader also wanted to do further checks on Russell Defreitas, the 63-year-old accused mastermind of the plot, and an unidentified confidential informant who had infiltrated the group, the documents said.

Abu Bakr declined to say if he knew the men, but also denied any involvement.

"I know nothing about these men, and I have nothing to do with whatever they are being charged for," he said in his first public comments since U.S. authorities disclosed the plot on Saturday.

Two of the suspects — Abdul Kadir, a former member of Guyana's parliament, and Kareem Ibrahim of Trinidad — are in custody in Trinidad. Nur was being sought by Trinidadian authorities. Defreitas, a U.S. citizen native to Guyana and former JFK air cargo employee, was jailed in the United States.

Abu Bakr's group, often accused of aiming to create an Islamic state in Trinidad, describes itself simply as a religious organization. The group stormed Parliament and took the prime minister and his Cabinet hostage in a 1990 rebellion that left 24 dead — the only Islamic revolt in the Western Hemisphere. The rebels eventually surrendered and were later pardoned.

It is not known to have international reach, although a member was convicted of trying to smuggle 70 assault rifles to Trinidad from Florida in 2005.

Abu Bakr faces charges stemming from a 2005 sermon in which he called for war against rich Muslims who refuse to pay zakaat, an Islamic tithe used to alleviate poverty. The following week, he was arrested by police who razed the group's compound and charged him with sedition and incitement to violence.

"You know why they are linking me with this so-called plot is to bias the minds of jurors who will be sitting in my case," he said.

Separately, a lawyer for the two men held in Trinidad said they would fight extradition to the United States. Ibrahim and Kadir made their initial court appearance Monday for extradition on one count each of conspiracy to commit a terrorist act against the U.S. government.

"We will be opposing extradition," said Rajid Persad, a lawyer who represents both men.

The judge set another hearing for June 11 to consider bail and scheduled an extradition hearing for Aug. 2.

Farid Scoon, another lawyer for the men, said they intend to seek bail.

The extradition fight could be a drawn-out affair. Ibrahim and Kadir could appeal all the way to the Privy Council in Britain, the highest court of appeal for the former British territory.

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The Associated Press contributed to this report.