Thousands of drivers were delayed yesterday afternoon after a dump truck flipped on its side on H-1 Freeway near the King Street exit, closing the main route to East O'ahu for about 3 1/2 hours.

Shortly before 1 p.m., a KD Construction dump truck traveling east crashed into the concrete median.

The top of the wall broke off, and concrete hit two cars traveling west. There were no major injuries reported.

Fuel from one of the truck's two 55-gallon diesel tanks spilled, stretching 100 yards along the road, said Kenison Tejada, Honolulu Fire Department spokesman.

"The cars that were on the freeway at that time had to go around the vehicle to avoid it, so they tracked some of the diesel," Tejada said, noting that the fire department's hazardous materials crew spread absorbent to soak up the spilled fuel.

The 39-year-old dump truck driver was arrested at the scene of the accident on suspicion of disorderly conduct, police said.

"He was arrested in mind for his safety," said Lt. Gerrit Kurihara.

"He was apparently agitated and continued to walk into traffic lanes. When they tried to bring him to an area away from (traffic), he got more agitated."

The driver reportedly swerved to avoid colliding with a car that had cut in front of him. Police are still investigating what kind of car it was and are looking for witnesses who saw the car.

Police took the driver to The Queen's Medical Center where he was treated and released, police said.

KD Construction officials still need to determine if the accident was mechanical or accidental, said Doug Sarte, a safety officer for the company.

"The first thing we thought of was, 'Is anyone hurt?' The first thing they told us was 'no,' " Sarte said.

"We'll do all our investigations along with the police officers and then go from there."

After the accident, police diverted eastbound traffic off H-1 at the King Street exit. Traffic along the surrounding streets then slowed to a crawl.

The Kapi'olani Boulevard onramp remained open.

Between the King Street exit and the Kapi'olani Boulevard onramp, four fire trucks surrounded the 10-wheeled dump truck.

In the far left lane, 30-foot skid marks showed where the driver had hit his brakes and veered left into a concrete barrier.

A yawning gap in the retaining wall marked the point of impact.

A state Department of Transportation maintenance crew had to cut out parts of exposed rebar from the retaining wall before the lanes could be reopened.

By 3 p.m. tow trucks rmighted the truck and a DOT contractor began draining the truck's fuel and hydraulic fluid.

DOT maintenance workers used gas torches to cut away the rebar, and lanes were reopened shortly after 4:30 p.m.

Six motorcycle officers and 12 patrol officers were on the scene to investigate the accident and control traffic, Kurihara said.

"We're very fortunate the truck didn't impact another vehicle directly," he said. "Some people are very lucky today."

Reach Robert Shikina at rshikina@honoluluadvertiser.com.