
There were no immediate reports of injuries.
The airport is a major international hub near New York City.
"Newark Airport is temporarily closed due to deployment of emergency chutes on a plane with an apparent engine fire," a post on the airport's official Twitter account said. "No injuries reported."
A passenger posted video of the plane on the tarmac surrounded by vehicles with flashing lights. "Just had to evacuate my @united flight using the slide," the user tweeted using the handle @lo_toney.
United Airlines Flight 1579 bound for San Francisco halted its take-off as it was taxiing on the runway, local media reported. It was due to depart at 9:22 pm (0122 GMT Wednesday).