Investigators announce cause of blaze that tore through high school under construction in Worcester

Investigators have announced the cause of a massive blaze that tore through a high school that is under construction in Worcester on Monday.

A piece of welding equipment ignited piled roofing material at the site of the new Doherty High School building, according to the Worcester Fire Department.

The fire broke out shortly after 3 p.m. and crews struggled to knock down the flames because the blaze broke out on the fifth-floor of the construction site, prompting the use of aerial equipment.

Video from the scene showed gigantic plumes of black smoke billowing into the air as the fire raged.

One worker at the scene was transported to the hospital with non-life-threatening injuries.

The site’s required hot-work permit from the city had lapsed at the time of the incident, and investigators say a new permit will not be granted “until an acceptable construction safety plan is presented and approved.”

An inspectional service team is working to assess the damage and determine the stability and integrity of the affected parts of the structure.

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