The Washington, D.C., Metro pulled more than half of its rail cars Sunday night after a National Transportation Safety Board (NTSB) investigation found multiple axles out of compliance with manufacturing specifications.
The Metro suspended its latest model, the 7000 series, just before the Monday morning rush. The board reportedly found the issues after investigating a Blue Line derailment, according to the Washington Metrorail Safety Commission, a congressional agency focused on Metro safety.
The 7000 series makes up about 60 percent of the 1,200-car fleet run by the Metro, officially called the Washington Metropolitan Area Transit Authority.
“As Metro continues to work closely with the Washington Metrorail Safety Commission and NTSB and more information develops, we will update the public about service for the remainder of this week,” it said, according to The Washington Post.
The authority added that it will operate about 40 trains Monday, “offering a basic service pattern on all lines of trains departing about every 30 minutes.”