A massive fire caused extensive damage Sunday night to the Kings entertainment complex, the first major tenant that was set to open April 28 at the 3rd Ave. retail complex in Burlington.

It took firefighters from Burlington and six surrounding towns more than seven hours to get the blaze under control, Burlington Assistant Fire Chief Michael Patterson said. Portions of the metal roof collapsed.

"The building is most likely a total loss," Patterson said. "A lot of the fire was located close to the roof of the building and it was difficult to gain access."

A passerby reported smoke coming from the roof of the building at 9:40 p.m. No workers were on-scene at the time and no injuries were reported, Patterson said. The cause is being investigated by the state fire marshal’s office.

The 27,000-square-foot building is the largest of the Kings bowling-themed complexes in Massachusetts owned by nightclub czar Patrick Lyons. Others are located at Legacy Place in Dedham, MarketStreet Lynnfield and Boston’s Back Bay. The complexes contain 10-pin bowling lanes, billiard tables, full-service restaurants and sports bars.

3rd Ave. is a 300,000-square-foot outdoor retail complex anchored by a Wegmans supermarket scheduled to open in September. The complex is being developed by Nordblom Co. of Burlington, which owns the 203-acre Northwest Park property on Middlesex Turnpike. Eight restaurants and 20 specialty retailers were scheduled to open this year. The project also will include a 200-unit apartment complex scheduled to open in 2016.

Nordblom tore down 11 aging office buildings to make way for the stores and apartments in the heart of an office park originally developed in the 1950s.

Email: sadams@thewarrengroup.com