ALAMEDA — A fire that damaged a popular Japanese restaurant early Friday morning was likely caused by an electrical malfunction, according to its general manager.

It remains unclear, however, just when Kamakura, 2549 Santa Clara Ave., will reopen.

“I am not holding my breath,” said Wayne Yamato, the general manager and son of Faith Yamato, the 92-year-old owner. “We are trying to get going and stay positive. But it’s going to be a while.”

The fire erupted about 4:12 a.m. in the kitchen and pantry area of the restaurant.

Yamato thinks the fire may have been sparked as a result of a malfunction in an ice machine. A washer and dryer are also in the area where it began, he said.

Alameda Fire Capt. Jim Colburn said it took 21 firefighters about 10 minutes to control the fire, which caused extensive damage to the kitchen as well as smoke damage to other parts of the family-owned restaurant.

There was also some smoke damage to adjacent businesses but no fire damage, Colburn said.

The exact cause of the fire remains under investigation. A damage figure has not been determined, according to firefighters.

“It’s pretty major,” Yamato said.

About 20 people work at the restaurant, which opened in 1981. It has won several awards, including being named Alameda’s best restaurant for sushi in 2013.

Steve King, the co-owner of the Whales & Friends store in Alameda, has set up a GoFundMe account for the restaurant.

“As a longtime patron of the Kamakura restaurant, I’ve decided to open a GoFundMe campaign to help the Kamakura reopen and to support the restaurant’s employees while they’re out of work,” King said in an e-mail.

The account is located at gofundme.com/kamakura-restaurant-restoration.

The restaurant had closed at 9 p.m. Thursday and no one was inside when firefighters responded.

No injuries were reported.

The restaurant will need to get a health department clearance before reopening, authorities said.

Streets in the area were closed while firefighters were at the scene.