The Derry Fire Department is investigating the cause of a three-alarm fire that occurred at an industrial complex on the corner of Maple and Elm streets Monday night.
The fire at 35 Maple St. caused the closure of four local businesses: Linc’s Autobody, Sportwagen Mechanic Shop, New England Tanya Finishes and Industrial Equipment, and took 75 Derry and mutual aid firefighters four hours to subdue and involved several local and state agencies.
Derry Fire Battalion Chief Michael Gagnon said to his knowledge, this was the largest Derry fire since the 1990s.
Crews were dispatched to the property at 8:01 p.m. following several simultaneous 9-1-1 calls, according to a press release from the Fire Department. Car One, as well as Engines One, Two and Three, Truck Four and Medic Four initially responded and arrived in three minutes, according to the press release.
At the scene, crews found heavy fire coming from the one-story commercial building, which was “large and irregular in structure,” according to the press release. Fire crews determined that an “exterior defensive” attack was most viable due to the hazards in the building, which included extensive fire involvement and possible chemicals used for the businesses.

Fire crews deployed large diameter hose lines, portable master stream devices and elevated aerial master stream devices on the front and back sides of the building. Fire crews used an excavator to overhaul the remainder of the building to extinguish hot spots. Fire personnel were expected to return to the scene Tuesday to look for more hot spots.
The building is a complete loss. A building across the street was evacuated, with residents returning once the fire was under control. Fire crews were able to keep the fire from spreading to surrounding buildings and vehicles, according to the release.
The building is owned by the Robert H. Shaver Trustees and the Robert H. Shaver Family Trust. It is valued at $306,000 and is 3,144 square feet.
There were no known occupants of the building and no injuries to fire personnel or civilians.
Derry Police assisted with crowd management and traffic control. Public Service Co. of New Hampshire was called in to turn off the electricity inside the building and to disconnect overhead lines that were impeding the use of ladder trucks. The state Department of Environmental Services was called in because of the potential water and debris runoff and the impact to Beaver Brook, Horn’s Pond and Hood Pond. The DES was expected to return Tuesday morning to evaluate the effect on the area.
Mutual aid was supplied by Londonderry, Chester, Auburn, Windham, Manchester, Hampstead, Salem, Hudson, Plaistow and Hooksett, with station coverage by Nashua, Atkinson, Raymond and Sandown.
The fire remains under investigation by the Derry Fire Prevention Bureau and the New Hampshire State Fire Marshal’s Office.