A man in an apparent mental health crisis halted train service for almost half an hour and triggered a multi-agency response after he walked onto Silver Line tracks over the Capital Beltway.

Fairfax County Police officers were dispatched at approximately 11:32 a.m. on Wednesday to an area near the McLean Metro station after reports of a passenger experiencing a medical emergency, according to FFXnow. The train stopped at the McLean station, where Metro employees were evacuated onto the platform. The man, however, continued toward the Tysons station before climbing onto the tracks above I-495.

The Fairfax County Police Department deployed its Fairfax 1 police helicopter and a mobile crisis unit technician to the scene after first responders reported concerns about threats of self-harm, according to scanner traffic. Fairfax County Fire and Rescue and Metro Transit Police also responded.

Metro cut power to the electrified third rail on both sides of the track and stopped all trains between the Tysons and McLean stations.

"UPDATE: Silver Line: Trains are temporarily not running between Tysons and McLean due to a trespasser on the tracks at Tysons. Customers will experience delays in both directions," the agency announced on social media.

Some trains offloaded passengers at East Falls Church and Greensboro stations to reduce congestion, and a shuttle bus was provided, according to a Metro spokesperson.

Metro Transit Police officers took the man into custody at approximately 11:55 a.m., walking him off the tracks at the McLean station. He was transported to Reston Hospital Center for treatment.

Service between Tysons and McLean resumed by 12:06 p.m., though Metro warned riders would experience residual delays in both directions.

No charges have been announced. The man's identity has not been released.

About mobile crisis units

The mobile crisis unit deployed during the incident is part of the Fairfax-Falls Church Community Services Board's Emergency Services program. The CSB operates two mobile crisis units that provide on-scene evaluation and intervention for cases where police, fire and rescue, or other agencies request mental health consultation. The units operate from 8 a.m. to midnight daily.

Residents experiencing a mental health or substance use emergency can call CSB Emergency Services at 703-573-5679 (TTY 711), available 24 hours a day. The 988 Suicide and Crisis Lifeline is answered locally by the Northern Virginia Crisis Call Center; the local direct line is 703-527-4077.