By ASHRAF KHALIL
WASHINGTON (AP) — The regional train system serving the Washington D.C. area will remain on drastically reduced service levels through at least the end of this year. This comes as authorities grapple with a safety problem that has forced the majority of the trains out of service. Officials announced Monday that there were no set timelines for the return of the 7000-series train cars, which comprise about 60% of the fleet. A plan to bring older cars back into service has been delayed by a shortage of parts due to the global supply chain crisis.