Kauai firefighters extinguished a 42-acre brush fire that shut down Kuhio Highway and Leho Drive in Wailua early Monday morning, a county spokeswoman said.

The fire broke out in an open field near the Aloha Beach Resort shortly before midnight Sunday.

Firefighters brought the blaze under control by 3 a.m. and extinguished it by 4 a.m.

No injuries were reported in the incident and no structures were damaged.

Police shut down all lanes of Kuhio Highway and Leho Drive for roughly three hours to allow fire crews to respond. The roadways were open to alternating traffic flow by 3 a.m., and fully reopened by 4 a.m.

The cause of the fire is under investigation.