New York (CNN) -- Closing arguments could begin Thursday in the trial of a man accused of trying to to detonate a bomb in the New York subway system.
Prosecutors say Adis Medunjanin, a Bosnian-born American, conspired with admitted terrorists Najubullah Zazi and Zarein Ahmedzay to detonate bombs in New York subways in 2009.
Medunjanin is the only one of the trio on trial as the two alleged co-conspirators in the case have pleaded guilty.
Earlier in the trial Zazi, who is believed to be the mastermind, calmly told a jury how he acquired the ingredients to make the bombs.
If the attack was against the United States, then it was "moral," Zazi said.
Zazi said the group was trained in Pakistan by al Qaeda in 2008 and 2009 and then returned to the United States with instructions to attack.
Authorities widely regard the plot as the most serious al Qaeda attempt to launch an attack on American soil since 9/11.
Medunjanin's lawyer, Robert Gottlieb, has disputed prosecutors' claims and said in opening statements that prosecutors have used incediary rhetoric to inflame the jury.
"The truth is Adis Medunjanin is not a terrorist. ... In this case, the government is just wrong," Gottlieb said.