A kitchen fire at Otto Pizza at 576 Congress St. in Portland on Sunday caused significant water damage and will force the popular pizzeria to close for at least a few days.

Deputy Fire Chief Terry Walsh said the fire broke out shortly after 10 a.m. in the store, which is located near Congress Square.

Sprinklers in the three-story building, which also houses Otto’s administrative offices on the upper floors, turned on and kept the fire from spreading. However, the water damage caused by the sprinklers was widespread and forced the business to close Sunday, Walsh said.

“We’d still be there if the sprinklers hadn’t gone off,” Walsh said Sunday evening. “There is a lot of water damage and some smoke damage.”

Otto Pizza operates several shops in Greater Portland, including one on 250 Read St. and one at 225 Congress St. in Portland, two shops in South Portland and one in Yarmouth.

Eric Shepherd, a spokesman for Otto, described the damage as significant enough that the shop may have to be closed for a few days.

“We hope to open as soon as we can, but it is too early to know when that might be,” Shepherd said in an email. “Ownership and key staff are on hand today to help get everything back to normal as soon as possible.”

Shepherd urged customers to follow Otto on social media, which is how the pizza chain hopes to keep loyal customers updated on its progress.

Walsh, the deputy fire chief, said Otto’s employees were doing food preparation work when a connecting pipe to the oven caught fire around 10:07 a.m. The fire spread into an exhaust pipe that connected to the upper levels of the brick building.

All of the workers got out safely, but Portland police had to shut down Congress Street to traffic for more than an hour, Walsh said.

Three fire engines, three ladder trucks, a rescue truck and two ambulances responded.

Dennis Hoey can be contacted at 791-6365 or at:

dhoey@pressherald.com