Fire rages near NSW school

A Blue Mountains school has gone into lockdown as a fire rages in bushlands nearby.

Fire crews were on standby at Warrimoo Public School on Friday as firefighters tried to contain the blaze.

An aircrane was deployed in the area and there was a police escort for the school bus home.

NSW Rural Fire Service spokesperson Matt Sun said parents were being given supervised access to children.

"There's no direct homes at threat," he said.

"We are asking residents in the area to remain vigilant."

He said about 50 fires burning were burning across NSW and the vast majority were contained.