Illegal fireworks are being blamed for a massive fire that destroyed 14 boats and damaged several others at a boat storage facility on the north shore of Lake Union.

Firefighters found 14 boats engulfed in flames when they arrived at the fire at Lake Union Skylaunch Marina shortly after 10 p.m. on Thursday.

“This spread quickly but with heroic effort of Seattle Boat Company staff, we have prevented a much worse potential circumstance,” said Alan Bohling, CEO, Seattle Boat Company. “We are thankful for an outstanding team who reacted professionally and quickly in this extraordinary circumstance.”

There were no reports of injuries. Damage is estimated at $1.5 million.

Authorities say the fire was under control in about 10 minutes. The cause is under investigation, but Bohling said in a news release that “we believe that an errant firework from the hillside above landed inside a Skylaunch vessel.”

The Associated Press contributed to this report.