Nobody was allowed to enter Tariffville Elementary School on Thursday afternoon because of police activity in the area.
The school is located on Winthrop Street.
Simsbury police said they were called to the Willow Arms apartment complex on Elm Street after receiving anonymous threats to a person and police.
They had been searching the complex for a few hours.
At about 6 p.m., Simsbury police said they believe this was a 'swatting' incident, also known as a hoax.
Apartments at 55 Elm Street in Tariffville has been checked by police. No victims or threat found. Determined a swatting incident.— Simsbury Police (@Simsbury_Police) September 15, 2016
School officials said the building was in 'lock-out' mode. As of about 4 p.m., officials were slowly clearing out the school.
Police said there was no threat to the school, however precautionary measures were taken to ensure safety of students and staff.
For clarification, no threat to school, precautionary measures taken to ensure safety of students and staff.— Simsbury Police (@Simsbury_Police) September 15, 2016
Parents at the school said they received an email notification around 2:45 p.m., letting them know dismissal would be delayed.
Some students were able to leave on the bus, but an officer on scene said the walkers were being kept inside the school.
"It was pretty scary because...they didn't know exactly what was going on at first," said parent Shannika Arnold.
People who live at the Willow Arms apartment complex were watching on Thursday as investigators searched every apartment.
"It was pretty scary. Especially when it's your house and where your kids lay and all your personal items and you don't know whose there and what they're doing," Arnold said.
Investigators are still trying to figure out who made the threat and why.
Anyone with information should contact police at 860-658-3141.
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