Firefighters are responding to a blaze in a 25-story Los Angeles residential building. Authorities say there are reports that an unspecified number of persons jumped.

Firefighters swarmed the building on the city's west side Wednesday morning and people could be seen on the roof as flames and smoke rise from the sixth floor.

Fire Department spokesman Brian Humphrey says an undetermined number of persons were reported to have jumped from that or nearby floors. A large inflatable bag is set up on the ground on one side of the building. A Fire Department helicopter is hovering overhead.

"Persons (number undetermined) have reportedly jumped from that or nearby floors," fire department spokesman Brian Humphrey wrote on Twitter.