Groton City police and state police spent hours Thursday and into Friday morning on Allen Street for an investigation.
We still have not been told what it is they're investigating.
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Police said they did collect some items from the scene and sent them to a lab to be analyzed. They would not say what they found, but a police spokesperson called the items "unusual." The spokesperson said they did not find a body or any human remains at the location.
Police said they did not know if this situation is connected to any other cases in the area.
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Regardless, the Groton neighborhood is the focus of another police investigation.
"Not again, these things happening are just unusual and hope they can come to an end at some point,” Dan Vandyne, who lives near the scene, said.
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Groton City police, detectives and the Connecticut State Police Major Crime Unit have had Allen Street closed from around 1:30 p.m. Thursday into Friday morning, focusing on an apartment complex.
A neighbor said police were there until around 4:30 a.m. on Friday.
They were seen going in and out of the building, taking photos, and some wearing what appears to be hazmat suits.
“It's very surprising the things going on,” Vandyne said.
It's unclear what police are investigating and what a concerned citizen saw that led to this scene.
Police say they don’t know whether this is connected to other ongoing investigations in the community.
This scene is only a couple of hundred feet away from the area where police found the remains of a woman a month ago.
They say they're looking for the public's help in trying to identify her.
"The fact that there's so much police presence around right now and the fact that it’s right across from where they found the other body, it's just really scary,” Sara Lambert, of Waterford, said.

That's a situation that has rattled the surrounding area.
"It’s really eerie to see all of this,” Brynn Holmes, of Waterford, said.
With an hours-long investigation just a stone's throw away, people in the community say they feel they have more questions than answers.
"It's just scary now for [the] future,” Lambert said.
"How is it all not tied together?" Holmes said.
There were human remains found in Danielson last week, but Connecticut State Police confirm there is no known connection between that case and the situation in Groton at this time.