A man and woman were fatally struck by a Manhattan train Tuesday morning — after one may have tried to stop the other from committing suicide, authorities and police sources said. 

The 44-year-old man and 63-year-old woman were riding between cars on a moving northbound L train at West 14th Street and Sixth Avenue just before 10:30 a.m., according to cops and the sources. 

Witnesses told investigators it appeared one of the victims may have slipped onto the tracks in a suicide attempt — and the other fell while trying to grab them, police sources said.

Both were pronounced dead at the scene, police said. 

The relationship between the two was not immediately known.

Mayor Eric Adams responded to the scene and was briefed on the incident.

Photos posted to the City Hall Twitter account show Hizzoner wearing a jacket emblazoned with “Mayor Adams” on the back as he walked through the station, joined by apparent staffers. A photo shows him speaking with a cop.

L train service between Manhattan and Brooklyn was snarled as police continued to comb the track area for evidence hours after the deaths.

The latest update, posted by the MTA at 1:10 p.m., indicates that service had “just resumed.”

If you are struggling with suicidal thoughts or are experiencing a mental health crisis and live in New York City, you can call 1-888-NYC-WELL for free and confidential crisis counseling. If you live outside the five boroughs, you can dial the 24/7 National Suicide Prevention hotline at 988 or go to SuicidePreventionLifeline.org.