Updated

Computer network problems are delaying a pretrial hearing at Guantanamo Bay in the case of five prisoners charged in the Sept. 11 terror attacks.

The hearing was to start Wednesday at the U.S. base in Cuba.

Legal teams were doing last-minute preparations when they lost access to a government computer network. Defense lawyer James Connell says officials blame the outage on a deadly freight train derailment in Baltimore that disrupted Verizon Communications service.

A military judge has postponed the hearing's start until Thursday at the request of the defense.

The pretrial hearing is expected to last several days as prosecutors and the defense duel over the rules for classified evidence and other matters in the case of the five men accused of orchestrating and planning the Sept. 11 attacks.