BOOTHBAY (AP) -A spectacular fire Friday destroyed a commercial boatyard that specialized in tug boats, reducing the wooden harborside structure to ashes and twisted metal.

The 50,000-square-foot building at Washburn & Doughty Associates was rocked by a series of explosions as flames ripped through the facility. One firefighter was treated at the scene for heat exhaustion.

“I’ll tell you, it was some hot. The heat was unbelievable,” said Scott Carpenter, who works for a crane company contracted by the shipyard. Like the other 100 employees, Carpenter got out with his life as flames raced through the structure.

In addition to the main boat-assembly building, the office, shed and storage buildings were destroyed, Chief Tim Pellerin of the Lincoln County Emergency Management Agency said. Speaking to reporters in Portland, Gov. John Baldacci put the property damage at $30 million.

The boat builder in East Boothbay serves as a year-round economic linchpin in an area that’s heavily dependent on summer tourism.

“Hopefully, they’ll rebuild,” said Ed Shaw, who worked at the shipyard off and on before his retirement. “The industry needs them.” His wife, Betty, said the village had lost a treasured piece of history in addition to a major employer.

The blaze sent a plume of black smoke skyward, and about 200 homes and businesses near the boatyard were evacuated as fire crews and ambulances from two dozen towns in four counties converged on the scene. Specialists in hazardous materials were also called in.

Two tugboats were under construction in the building that was leveled. Another vessel that was in the water outside the boatyard was saved.

The boatyard’s operations manager, Lee Smith, said the company’s first priority is to launch the nearly completed tug within the next couple of weeks.

Smith, who was in the pilot house of the new tug when the fire broke out, said the company would conduct an internal investigation and also cooperate with fire officials to determine the cause. He also said employees were being asked to show up at the site at 7:30 a.m. Monday to discuss a transition plan that was to be drawn up during the weekend.

“This is going to be a rebuild operation,” said Smith.

The fire broke out just days before the company was to begin a $5 million expansion, said Smith.

While specializing in tugs, Washburn & Doughty has also built passenger vessels, fishing boats, barges, ferries and research vessels.

The intense fire started around 9:30 a.m., and black smoke could be seen from the bridge linking Wiscasset and Edgecomb, about 10 miles away.

“I’ve never seen smoke like that,” said Kristina Ford, who lives near the boatyard. The fire, she said, was “just obviously unstoppable. It was just so huge.”

Ron Riml, a retired police officer, showed pictures of flames shooting 30 feet above the roof as he watched from the top floor of his house several hundred yards away.

The scene was “almost like the Hindenburg as the frame and everything went up in flames,” he said.

“It went quickly, and once it went quickly there were a lot of explosions,” Riml said.

Gov. John Baldacci phoned Smith at the scene to discuss the damages, and was briefed on the fire by the Maine Emergency Management Agency.

He pledged to provide whatever state support is needed to help the company and the community recover.

“The state stands ready to provide whatever support is needed to fight this fire, and to help Washburn & Doughty and the community recover,” the governor said from Augusta.