The pipe exploded at Fifth Avenue and East 21st Street just after 6:40 a.m.
Watch: Raw footage of pipe explosion
The blast blew a large hole in the middle of Fifth Avenue, sending chunks of asphalt into the street.
ABC11's sister station WABC has learned multiple manholes exploded from West 19th Street to West 21st Street.
There have been no immediate reports of injuries.
FDNY is inspecting other manholes in the area.
FDNY has a second alarm response, NYPD has a Level 1 mobilization for crowd control.
Several buildings in the immediate area have been evacuated as a precaution.
Con Edison is responding. The city is setting up a command post at Fifth Avenue and 22nd Street.