A former employee of the Massachusetts Society for the Prevention of Cruelty to Animals took responsibility this morning for setting a fire that caused no deaths or injuries but seriously damaged the nonprofit organization’s animal hospital last year, Suffolk County District Attorney Daniel F. Conley announced.

WILLIAM FITZGERALD (D.O.B. 4/19/58) of Plymouth pleaded guilty to arson and causing injury to a firefighter for setting fire to the MSPCA-Angell Memorial Animal Hospital on South Huntington Avenue late in the evening of Feb. 19, 2010.

Suffolk Superior Court Judge Carol S. Ball sentenced Fitzgerald to four years probation, ordering that he stay away from all four MSPCA locations and employees in Boston, Centerville, Methuen, and Nantucket; that he complete 100 hours of community service; and that he undergo mental health treatment as deemed medically appropriate.

Fitzgerald was further ordered to reimburse the MSPCA for the $8,177 in unemployment benefits that the non-profit organization paid Fitzgerald before his benefits were denied, and that he pay restitution in the amount of $24,000 in fire-related damages.

“From that night in 2010 through today’s resolution, MSPCA officials’ first concern has been for the health and well-being of their employees and the animals they protect,” Conley said. “Like all of us, they were thankful that first responders arrived as quickly as they did and that no creature, human or otherwise, was hurt or worse. Moreover, their compassion even for the defendant was a powerful reminder of their kindness and humanity throughout the duration of this case.”

In an impact statement today, Brian Adams, an MSPCA-Angell spokesperson, told the court that on the night of the fire dozens of employees were present and more than 200 animals were in the hospital’s care that night.

“Through his dangerous and irresponsible actions Bill Fitzgerald jeopardized the public’s faith in us as a safe environment for animals and our colleagues,” he said. “The extent of damage that Bill Fitzgerald has done to the organization will not be fully comprehended for some time.”

Adams added that Fitzgerald’s actions created “an atmosphere of fear” among the staff and that “to have had the fire begun from one of our own went to the heart of the trust placed in our staff members. Until this day, and for some time ahead, the damage caused by Bill Fitzgerald is still being cleaned up. It is immeasurable and possibly irreparable.”

In a statement, Carter Luke, president of MSPCA-Angell, thanked Conley’s office, the Boston Fire Department, and the Boston Police Department for having a “full appreciation for the seriousness of this crime,” and conducting “a thorough investigation and resolution to a terrible act of arson.”

“Due to the installation of a state-of-the-art fire prevention system,” he continued, “the animals in our care and our staff members remained safe as Boston’s firefighters quickly put down the blaze. The men and women who fought the flames, investigated the arson, and saw that the man responsible will receive the help he needs should be commended for their work. It is all too often that such daily heroics go unnoticed. On behalf of the MSPCA-Angell, the animals in our care, and our staff members I wish to thank them for their continued work to keep our communities safe.”

Had the case proceeded to trial, Assistant District Attorney Julie Higgins – a member of Conley’s Senior Trial Unit and his point person for arson-related offenses – would have proven that Fitzgerald, a former MSPCA manager of building and grounds, started a fire on the fourth floor of 350 South Huntington Ave. late on the evening of Feb. 19 with the intention of taking credit for putting it out. Fitzgerald did not intend to hurt or kill anyone, prosecutors acknowledged.

At the time of the conflagration, the Jamaica Plain building contained most of the agency’s offices, sheltered more than 200 animals, and served as a residence for a number of resident veterinarian students. The building was evacuated before any animals or staff members were injured, but the fire, smoke, and water caused major damage and destroyed files that dated back to the 1930s.

Following a three-month investigation led by Boston Police detectives, the Boston Fire Department Fire Investigation Unit, and Suffolk County prosecutors, a Suffolk County Grand Jury indicted Fitzgerald in May 2010.

Fitzgerald was represented by attorney Kevin Reddington.