The assault took place aboard a Manhattan-bound A train, police said.
The victim's condition was not immediately clear, and B, C, A and D lines were affected, the FDNY said.
A witness who saw a child being yelled at was hit in the head with a bottle, police said.
The 6, 7, A, C, D, E, F, J, M, N, Q and R trains are slated for service disruptions this weekend.
Police said they were alerted after a straphanger noticed the sleeping gunman.
Shawn Howard of the Bronx attacked three people on the A and C trains, police said.
DNAinfo is collecting your images on Instagram to show the range of daily commutes.
The 1, 2, 3, 5, 6, 7, A, C, D, E, F and 42nd Street Shuttle will all be affected.
The muggers fled at Columbus Circle, police said.
MTA is modifying service on 1, 2, 4, 6, A, C, D, E, L, N and R over the weekend, so plan accordingly.
The 2, 3, 4, 5, 6, 7, A, C, D, E, F, L, Q, R and 42nd Shuttle will all be impacted.
The 2,3,4,5,6,7,A, F, L, Q and S trains will be affected by the modifications, MTA says.
Trains along several subway lines were disrupted because of a power outage, officials said.
The 4, 5, 6, 7, A, C, E, Q and the 42nd Street shuttle will be disrupted this weekend.
Bloggers and filmmakers with "Internets Celebrities" highlight food on the A line in "Food Warriors."
Get our daily Afternoon News Update
Thank you for signing up!
Would you like to sign up for additional newsletters?
Thank you for signing up for additional newsletters.