Metro to test backup software

WASHINGTON, D.C. (AP) - Metro officials are preparing to test software developed to back up the system meant to prevent train crashes.

Metro officials said that a test for the software is planned for Monday's morning rush hour.

After a fatal crash in June, the National Transportation Safety Board told Metro that its crash-avoidance system was inadequate and called for them to develop a backup.

Investigators have not announced the cause of the crash, but there has been a focus the automatic train control system, designed to keep trains a safe distance apart.