Emergency crews on Tuesday returned to the scene of a large brush fire in Rye as investigators work to figure out how it started.

Firefighters were still extinguishing hot spots at the Marshlands Conservancy after a fast-moving, smoke-billowing brush fire charred several acres on Monday.

The county Parks Department owns the property, which spans 147 acres.

Firefighters on scene say one of the reasons the fire was able to be put out so quickly and effectively was because the FDNY was conducting a training drill on the Long Island Sound when the blaze broke out.

Investigators have not yet determined an official cause, but some suspect it could have been started by a group of people who may have been smoking cigarettes.