"Black Bear siting in Greenfield Hill and the University area. Be careful out there and follow police guidelines," Tetreau Tweeted at @miketetreau at about 2 p.m.
"DEEP said to leave him alone, and that's what we're doing," said a spokesman at the Fairfield Police Department, referring to the state Department of Energy and Environmental Protection, which is the expert in all bear-related matters.
He said the bear had been spotted running through the neighborhood and all over town.
The first selectman's office sent out a Code Red Alert to residents living in the areas where the bear was spotted.
"It's not Paddington, we know that," said an employee in the town offices.
And just before 3 p.m., Fairfield resident Michael T. Borruso said via Twitter @MikeBorruso that the bear was up a tree in his neighborhood.
In a series of Tweets, he shows the bear sitting in a tree, which is surrounded by police, and taking a nap in the branches.
"There's a bear across the street," he said via Twitter. "Police have the bear surrounded. It's up a tree."
Brianna Amicone also photographed the bear, which went up a tree behind a house on Denise Terrace.
Police confirmed that a black bear was reported roaming in both the Greenfield Hill and Fairfield University areas Thursday morning.
Also on Thursday morning, the Westport Police Department received two separate reports of bear sightings from residents whose properties border the Merritt Parkway.
"The mere presence of a bear does not necessitate its removal," the police statement said. "In most cases, if left alone, the bear will make its way to a more natural habitat. Removing food attractants, such as bird feeders, reduces the chance that bears will go near homes.
"The DEEP seldom relocates bears. An exception may be made to remove a bear in an urban location when there is little likelihood that it can leave safely on its own and when the bear is in a position where it can be safely immobilized," police said.
Bears are known to wander into heavily populated residential areas, according to DEEP. In Connecticut, adult males weigh from 150 to 450 pounds, while females weigh from 110 to 250 pounds. Yearlings weigh 45 to 100 pounds. Adults are 5 to 6 feet tall.
Residents have spotted bears in a number of towns this spring and summer, including Danbury, Darien, Norwalk and Greenwich.
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