New York (CNN) -- The men on trial for plotting explosions at John F. Kennedy International Airport planned a blast that would "blow through the airport and through to Queens," a witness testified Thursday.
Donald Nero said he had been involved with defendants Russell DeFreitas and Abdul Kadir in the initial stages of planning the attack. He told the court he participated in several meetings held in Guyana, his native land, in late 2006.
In those meetings, he said, DeFreitas and others conspired to bomb jet-fuel supply tanks and gas pipelines at JFK, one of the United States' busiest airports.
DeFreitas and Kadir were charged in 2007 with conspiracy to attack a public transportation system, conspiracy to destroy a building with fire and explosives, conspiracy to attack aircraft and aircraft materials, conspiracy to destroy an international airport and conspiracy to attack a mass transportation facility. Kadir was also charged with surveillance of a transportation facility.
They sought to inflict "economical damage, destruction of airport property and loss of life" Nero said.
He testified that "DeFreitas said the plot would be payback for the United States sending weapons to Israel to kill Palestinians."
Nero said DeFreitas told those gathered at these meetings that he personally loaded U.S. "bombs, missiles and planes" bound for Israel while working at JFK.
DeFreitas is a United States citizen and former JFK cargo worker. Kadir is a citizen of Guyana who has served as a member of Parliament there.
A third defendant, Abdul Nur, pleaded guilty Tuesday to providing material support to terrorists. Nur is also from Guyana.
Prosecutors have said the men tapped into an international network of Muslim extremists to develop the plot and start work toward carrying it out.
A criminal complaint accuses the men of obtaining satellite photos of the airport and using DeFreitas to conduct surveillance and identify potential targets and escape routes.
An informant secretly taped conversations in which DeFreitas allegedly described the symbolic importance of targeting JFK, the complaint says.
"Anytime you hit Kennedy, it is the most hurtful thing to the United States," he allegedly said, according to the complaint. "If you hit that, this whole country will be in mourning. It's like you kill the man twice."
All three men have been in U.S. custody for the past two years after a court in Trinidad and Tobago rejected their attempt to avoid extradition.
Their lawyers had earlier argued that Trinidad and Tobago law does not allow for extradition on terrorism conspiracy charges.
New York Police Commissioner Raymond Kelly has said officials were concerned not only about a possible attack on the airport, but also about an attack on the 40-mile aviation fuel pipeline that runs from a fuel tank farm at JFK through Staten Island, Brooklyn and Queens.
The trial is being held before federal District Judge Dora Irizarry in Brooklyn.
Nero, who also goes by "Dawud bin Massud," testified that he attended several meetings with people allegedly involved in the plot that included DeFreitas and others. Among them were two people identified only by the monikers "Longhair" and "Annas."
It later became apparent in court that both men were confidential informants for U.S. authorities who had infiltrated the group.
"Annas" appeared on the stand as a government witness later Thursday. His real name is Steven Francis and he said he is a native of the Dominican Republican who converted to Islam in the 1990s. Francis told the court he has worked as a confidential informant for several years infiltrating Muslim groups in New York.
Nero and Francis barely mentioned Kadir. Nero said he met Kadir once through the group, but said he did not see him at any of the meetings to plan the attack on JFK.
Nero described the different roles the men had in the plot. He said DeFreitas recruited "Annas" in New York and the two secretly entered JFK and videotaped airport hangars, fuel tanks and a guard tower they showed to the others in Guyana. Nero said he had the job of finding recruits in Guyana, while a businessman known as Neville "Talib" Rutherford played the role of financier.
Nero said the group tried to link up with Muslim radicals in Trinidad and Tobago, including Jama al-Muslimeen, a group that attempted to overthrow the Trinidadian government in 1990.
Nero also said the group sought out Azam Shukrijumah in Trinidad. Shukrijumah's name has been linked to al-Qaeda and to Najibullah Zazi, who is accused of being involved in another more recent terrorist plot targeting New York.
Although Nero said nothing came of the attempts to link up with Trinidadian radicals, those attempts gave him cold feet. After that, he said, the plot had fizzled by the spring of 2007.
He later heard that DeFreitas, Kadir and Nur had been arrested in Trinidad. He said the FBI and Guyanese authorities sought him out in 2008, and he agreed to come to the United States to help government prosecutors in the case in 2008. He has been in U.S. custody since then.
He told the court that he pleaded guilty to providing support to the alleged bombing plot. In exchange for his testimony Thursday, prosecutors have promised to write the judge in his case and detail the cooperation Nero provided, a move that could reduce his prison sentence, scheduled for later this year.
The court trial reconvenes on Tuesday July 6.
CNN's Hussein Saddique, Susan Candiotti, Julian Cummings and Nkechi Nneji contributed to this report