BREA (CBSLA) — Firefighters are getting a handle on two fires that broke out about a quarter mile apart along the Orange (57) Freeway in Brea early Wednesday morning and spread across the Los Angeles County line into the Diamond Bar area.

Fire in the area was first reported at 2:18 a.m. near Lambert Road, according to the California Highway Patrol, and authorities said as many as four fires later merged into two blazes that scorched a total of 15 acres. The fires were declared fully contained by 9 a.m.

There were no immediate reports of injuries and no structures were threatened.

All northbound lanes of the freeway and the Lambert Road on-ramp were closed during the firefight. Northbound lanes were also closed on the Los Angeles County side at Brea Canyon Road before reopening later in the morning. Two northbound lanes are expected to remain closed into Thursday.

More than 100 firefighters from surrounding fire agencies were on the scene and four water-dropping helicopters were deployed to help battle the blaze.

Authorities say the fires may have been deliberately set. A witness reported seeing a man with a white scarf around his face wearing blue jeans and driving a black sedan in the area of where a brush fire burned next to the northbound 57 Freeway, just north of Tonner Canyon.

These fires are just about 12 miles east of where Canyon Fire 2 destroyed dozens of homes and burned nearly 10,000 acres.

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)