Government officials are still weighing the possibility of using Washington, D.C.’s federal courthouse as a site for prosecuting Guantanamo detainees, the court’s chief judge said Thursday morning.

Chief Judge Royce Lamberth of the U.S. District Court for the District of Columbia said he has been in talks with the government about the significant security concerns related to bringing cases to Washington. He said courts in the Eastern District of New York and Eastern District of Virginia are also being considered as locations. The Obama administration chose Manhattan’s federal courthouse as the site to try alleged Sept. 11 mastermind Khalid Sheikh Mohammed, as well as four other plotters.