U.S. Attorney General Eric Holder on Wednesday flew to New York to huddle with his team that will be in charge of prosecuting and imprisoning the five men accused of plotting the Sept. 11, 2001 attacks.

GUANTANAMO-USA/The closed-door meeting at the federal courthouse in downtown Manhattan included the prosecutors from the Southern District of New York and Eastern District of Virginia as well as representatives of the FBI, Bureau of Prisons, the Marshals Service, and the New York Police Department, according to an administration official.

A spokeswoman for Holder declined to provide details about the meeting. NBC News reported on Tuesday that a grand jury was hearing evidence against the self-professed mastermind of the attacks Khalid Sheikh Mohammed.

The five men are not expected to arrive in New York until early next year at the earliest because first the Obama administration must give Congress 45 days advance notice about how they will secure the prisoners and address any security issues.

Holder has come under blistering criticism from Republicans for deciding to try the accused 9/11 conspirators in U.S. criminal court instead of a military court, arguing that they should not be brought to American soil from the U.S. military prison at Guantanamo Bay, Cuba.