Honolulu fire officials are investigating what caused a blaze to engulf a giant forklift at a busy Honolulu shipping pier Monday, sending up a smoke plume visible from across the city and prompting an evacuation of a quarter-mile area. Nimitz Highway was closed for more than an hour.

The 5,000-gallon propane tank that the lift was holding at the time did not catch fire, and no one was injured, officials say.

Young Brothers Ltd. reported evacuating up to 120 employees plus customers away from the lift to the mauka side of its Piers 39 and 40 operations. The blaze, at Pier 40, shut down operations for hours during one of its busiest shipping days of the week and delayed its Monday barge sail to Kawaihae, Hawaii island, until today, officials said.

Hawaii island customers will see a one-day delay in their cargo’s arrival, according to Dean Kapoi, the company’s vice president for terminal operations.

The largest-model lift at those piers, the Hyster 1150, or “hy-lift” for short, caught fire just as the operator lifted the propane tank to load it onto the barge, Kapoi said.

The operator set the tank down, turned off the lift’s engine and evacuated along with about 10 other employees working in the immediate area, Kapoi said.

Fire crews responded to the two-alarm fire at 8:02 a.m. and arrived at 8:05 a.m., Honolulu Fire Department spokesman Capt. David Jenkins said. Many of the firefighters came from the station just across Nimitz Highway, Young Brothers officials said.

Eleven units focused on cooling the propane tank as well as putting out the fire, according to a Honolulu Fire Department news release. They had it under control by 9:13 a.m. and lifted a quarter-mile evacuation zone affecting Nimitz Highway at 9:30 a.m.

The fire caused an estimated $870,000 in damage, including the destruction of the $750,000 forklift, Jenkins said. No significant amount of fuel was released into Honolulu Harbor, he added.

Young Brothers will have to finish an investigation before deciding what steps to take, Kapoi said. It was one of eight hy-lifts at Piers 39 and 40, he said. The company does preventive maintenance after using each hy-lift for 250 hours, Kapoi added.

Young Brothers reported reopening its gates to the piers at 1:30 p.m. “We’ve been down for about five hours, and that’s going to cause some problems once you let the floodgates open on a heavy barge day,” Kapoi said about two hours before the reopening.

Young Brothers’ other regular sailings to Nawiliwili Harbor on Kauai and to Kahului proceeded as usual, according to the company.

The forklift operator, meanwhile, appeared to be in “positive spirits” and “more concerned about his fellow co-workers as we evacuated the facility,” he said.

Kapoi said he could not recall “anything of this magnitude” at the piers in his 19 years with the company.