SOUTHBURY, Conn. (WTNH) – State police charged a 21-year-old man with arson on Wednesday for allegedly lighting the Southbury Training School on fire in December.

On Dec. 17, the Southbury Fire Department responded to the scene of a working structure fire on Village Road. Fire crews reported the building sustained catastrophic damage to the structure as the roof and walls collapsed into the basement.

Fire officials requested assistance from three other fire departments to help get the fire under control. Fire crews said that no one was injured in the fire.

The Connecticut State Police Fire and Explosion Investigation Unit were called to the scene to investigate the origin and cause of the fire. Investigators determined the fire was set intentionally by a person.

Police identified the suspect as Gregory Gulick of Southbury.

Gregory Gulick (SOURCE: Connecticut State Police Department)

Gulick had allegedly posted a video of himself on top of the Southbury buildings on Dec. 17 before the fire began. Police conducted several interviews relating to Guilick’s alleged involvement with the fire.

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A coworker of Guilick’s told state police that when asked how his weekend was, he said he spent time with friends and burned down a house.

When his coworker questioned him further about his statement, Gulick allegedly said he burned down a condemned house and that no one was living in. He allegedly told his coworker he went to the gas station and bought 10 to 15 gallons of gas that he later used to start the fire.

According to the police, Gulick told several other people that he’d started the fire. Police said in the conversations, Guilick admitted to burning down a home, but kept changing the location of where the fire occurred.

A witness who was traveling near the area of the Southbury Training School pulled into the parking lot as she saw flames.

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She saw three people sitting inside of a black car and took down the license plate as she thought the people were acting suspiciously. The woman said the man approached her car and asked her to move.

On Wednesday, state police arrived at Gulick’s home and conducted a search of the residence after collecting evidence that pointed Guilick as a suspect.

Police found clothing that Guilick was thought to be wearing when he took photographs at the property which were then seized by police. Police brought the clothing to be sniffed by an accelerative detector-rated police K-9. The K-9 responded positively to three pieces of clothing, according to state police.

When state police questioned Gulick, he admitted to starting the fire because he wanted to do something to honor his friend who died of an overdose. Gulick stated he wanted to “kill two birds with one stone,” as his friend had a pyromaniac and was interested in haunted houses.

Gulick was charged with criminal trespassing in the third degree, arson in the third degree and a conspiracy to commit criminal mischief in the first degree.

Gulick is being held on a $250,000 surety bond as he could not post bail. He is set to appear at Waterbury Superior Court on Thursday.

Two females from New Milford were allegedly with Gulick at the Southbury Training School property when he started the fire. One has been identified as Juliana Sullivan, 22, of New Milford. She has been charged with third-degree criminal trespass, third-degree arson and third-degree conspiracy to commit arson.

Juliana Sullivan (Source: Connecticut State Police)

Sullivan turned herself in on Saturday and posted a $50,000 bond, according to police. She is scheduled to appear in court on Jan. 18.

On Wednesday, state police arrested 18-year-old Julia Ninno of New Milford in connection to the fire. She was charged with third-degree criminal trespass, third-degree arson, and conspiracy to commit arson.

Ninno was released on a $50,000 bond.

State police said no additional arrests will be made and the case is now closed.