A vegetation fire near the El Dorado Nature Center Wednesday evening was intentionally set and a suspect is in custody, authorities said.

The two-alarm fire caused a traffic headache in East Long Beach and scorched about a half acre of land, fire officials said.

The blaze erupted at about 4:55 p.m. on the San Gabriel riverbed near East Willow Street.

A 43-year old man who was suspected of starting the fire was taken into custody, Fire Department spokesman Jake Heflin said. His name was not released.

“The fire remains suspicious and under investigation,” he said.

Westbound Willow remains closed between 605 Freeway and Studebaker Road while firefighters mop up the scene. Some spot fires had also ignited inside the nature center, which was closed when the fire started.

Orange County Air Authority provided air support, but ground crews were able to extinguish the fire by about 5:40 p.m., officials said.

Fire officials did have some trouble with water supply, and had to shuttle water from other fire engines, Heflin said.