TABERNACLE, N.J. (AP) — Authorities say fireworks sparked a fast-moving forest fire that has consumed thousands of acres in southern New Jersey.

The New Jersey Forest Fire Service said Sunday that “a fireworks device” set alight in the Wharton State Forest late on the Fourth of July started the fire. The blaze was spotted from a fire tower shortly after 9 a.m. Friday burning near Apple Pie Hill and the Batona Campground, which was evacuated as a precaution.

Officials asked anyone with information about the fire to call the state park police tip line. The forest fire service led the investigation in collaboration with state park police, the state division of fire safety and the Burlington County fire marshal’s office, officials said.

Authorities said Saturday that the blaze had burned an estimated 4,000 acres but they reported “substantial progress in getting it under control” and estimated that it was 65% contained. Officials said crews planned to monitor and improve containment lines.

Officials said earlier that crews were using a backfire operation to help combat the blaze, which involves burning areas ahead of the main fire in a bid to stop the flames from spreading. Several roads and trails have been closed.