Norwich — Police on Thursday arrested a 28-year-old Norwich man on arson charges in connection with an April 20 fire at an occupied building at 27 McKinley Ave. that injured four people, including a firefighter, killed three animals and caused $50,000 in damage.

Daniel G. Elliot-Villarreal, who is a resident of the four-family structure that burned, is charged with first-degree arson and first-degree criminal mischief. Police said he also was injured in the fire and was rescued by one of the firefighters as his apartment burned.

Police issued a statement about the arrest on Thursday but did not indicate how the fire, which was contained to a first-floor apartment, started.

Eight people were inside the building at the time of the fire. Three people suffered from smoke inhalation and were taken by American Ambulance to the William W. Backus Hospital for treatment. A Norwich firefighter sustained minor injuries which required medical attention. Two dogs and a cat died in the fire.

Elliot-Villarreal, after initial treatment at Backus, was transferred to Bridgeport Hospital Burn Center for a higher level of care.

The Norwich Fire Marshal’s Office, with assistance from the Connecticut Fire and Explosion Investigation Unit and Norwich Police Department fire investigators, conducted the investigation into the cause of the fire.

Detective Trooper Wayne Opdenbrouw and his dog Sprite, who can sniff out accelerants, helped determine the fire started in Elliot-Villarreal’s apartment, police said. Norwich Deputy Fire Marshal Lauren Cassidy ruled the fire “incendiary” and the investigation was turned over to Norwich Police Department Fire Investigators Officers Scott Dupointe and Robert Smith.

Elliot-Villarreal was arrested after his release from Bridgeport Hospital. He was held in lieu of a $100,000 court-set bond pending his court appearance Friday at Norwich Superior Court. Police said no additional arrests are anticipated.

Anyone with information regarding arson fires is asked to call the Norwich Police Department’s anonymous tip line at (860) 886-5561, ext. 4, or the Connecticut Arson Hotline at (800) 842-7766.