Groton — The Stonington High School senior prom came to an abrupt end Saturday night when someone sprayed an irritant into the air of the Mystic Marriott Hotel & Spa ballroom, causing coughing dancers to flee.

Three students were taken by ambulance to the hospital, where they were treated and released "and appeared fine when they went home," Principal Mark Friese wrote in an email to parents at 8 a.m. Sunday.

Groton Town police said Sunday that they had no update on their investigation.

Groton Town Police Sgt. David Miner said Saturday night that police received complaints of students having difficulty breathing about 9:45 p.m. Multiple firetrucks, police cruisers and ambulances responded to the hotel at 625 North Road.

Miner said someone had sprayed “some sort of airborne substance” similar to pepper spray. No lasting effects were expected, he said. 

Sophomore Zoe Main, said Sunday she was one of those affected by the irritant but did not need to go to the hospital. She said she and two of her friends, both of whom were transported to the hospital, were dancing in the back right corner of the dance floor when they were affected. 

"It felt like pins and needs in the inside of my throat. It was the weirdest feeling. I've never experienced anything like that," she said, adding that once she left the hotel she felt immediately better.

Main said her two friends, both girls, felt nauseous and one had difficulty with her asthma. 

On Saturday night, the hotel’s parking lots quickly filled with teens in tuxedos and gowns, some with bottles of water, others sipping from cups, milling about among the police cruisers and firetrucks.

“We were dancing and then the people in the front started coughing and choking,” senior Nicolas Turco, 18, said. He added that they couldn’t smell anything.

About 10:30 p.m., adults with plastic bags were allowed back into the ballroom to collect personal items, such as phones and shoes, that students had left behind. Police were investigating and no one had been arrested.

"Clearly this is not the way our students represent themselves, their school, or their town," added Friese who asked anyone with information that would helpful with the investigation to contact him at  mfriese@stoningtonschools.org.    

Superintendent of Schools Van Riley said Sunday night that there was no word yet on exactly what the substance was.

"We'll do the best we can to find out what happened," he said. 

Stonington Police Capt. Todd Olson said Sunday that he expects his department would be assisting Groton Town Police with the investigation.