Maui County firefighters will be working overnight to contain a brush fire near Kapalua Airport that burned at least 450 acres on Wednesday.

The Maui Fire Department said it responded to the fire mauka of the airport just before 11 a.m., and by 8 p.m. it was 50% contained..

MFD reported that the fire burned 450 acres Wednesday afternoon, but had no further updates on its size.

Six engine companies, three tankers, three helicopters, private bulldozers and tankers, and state personnel with access to firefighting equipment are fighting the fire.

Employees of a water treatment plant near the airport were evacuated, although no injuries or damage to structures were reported.

MFD said the cause of the fire is unknown.