Firefighters responded to two brush fires Thursday morning, according to the Maui Fire Department.

The first, near mile marker 7 on Honoapiilani Highway, was reported at 2:17 a.m. Crews arrived to find a blaze that stretched about 100 yards along the highway, with winds at 10 to 15 mph. They extinguished the fire, which burned less than an acre of grass and brush, at around 4:30 a.m.

The second fire, on the Wailuku side of Honoapiilani Highway at the intersection with Kuihelani Highway, was reported at 3:13 a.m. Arriving crews extinguished that blaze, which burned less than a quarter-acre of brush, shortly before 5 a.m.

Portions of Honoapiilani Highway were closed while firefighters were at work. An investigation into what caused the fires is ongoing.