BOULDER CREEK (CBS SF) — Calfire crews in Santa Cruz County on Wednesday evening were able to stop forward progress of a vegetation fire burning in a heavily wooded area in Boulder Creek, according to authorities.

The fire was burning just outside the CZU Lightning Complex burn area, according to Calfire officials.

ALSO READ: High Temps, Dry Conditions Raise Specter of Drought and Fire Danger Across the Bay Area

The Calfire CZU Twitter account first posted about the three to five acre vegetation fire burning near Greenvale Road and Highway 9 in Boulder Creek shortly before 5 p.m.

A short time later, they posted an image showing smoke rising the trees in the area of the so-called Fossil Fire, noting that the fire was burning in timber.

As of about 5:18 p.m., Calfire said forward progress on the fire had been stopped. Air support was making water drops on the fire.

Crews were able to keep the size of the fire to approximately three to five acres, Calfire said, holding the fire at the top of a ridge.

The cause of the fire is under investigation.