Starting Monday, F and M subway lines are switching routes, a change expected to impact more than a million riders daily. Transit officials believe it will help address major service concerns that have plagued the two lines for years.

The maniac who set a homeless man on fire on a Manhattan subway train early Monday morning is still on the loose, leading police to release surveillance images in hopes of tracking him down.

Federal prosecutors filed arson charges Friday against the 18-year-old Harlem man accused of setting a homeless subway rider on fire at Penn Station earlier this week. The charges come after investigators matched his face to body camera footage from a bicycle traffic stop a month before the incident.

A teenager is facing federal charges for allegedly setting a 56-year-old homeless man on fire on a New York City subway train.

A teen was arrested Thursday for allegedly setting a sleeping homeless man on fire on board a train passing through Midtown this week, law enforcement sources said.

Police released surveillance images Wednesday of the Midtown subway arson suspect whom they believe set a sleeping homeless man ablaze on Monday. According to police sources, the 56-year-old victim was dozing on the Harlem-bound 3 train just after 3 a.