Police have identified the owner.
"The child inadvertently left the item in the vicinity of the bridge with the intent of returning to retrieve the school project," Fairfield police said in a statement. "It has been determined that this was an unfortunate accident and there was no malicious intent."
The case is now closed, the statement said.
But Police Chief Gary MacNamara said the situation was taken seriously because of where the box was found on the bridge, which carries traffic and pedestrians over the Metro-North train tracks near the Fairfield train station.
The box looked like it could be a building or a robot - check out the photo above released by the Fairfield Police Department. One Daily Voice comment compared it to Bender from "Futurama." It appears to have a smiling face with clock hands.
The box was first spotted at 5:33 a.m. by a Department of Public Works employee on the pedestrian sidewalk of the Unquowa Road railroad overpass.
The Connecticut State Police Bomb Unit, which arrived at about 7:20 a.m., X-rayed the object and determined it was not an explosive.
The item was seized by the Fairfield Police for further investigation. The Detective Bureau wants to determine whether it had been placed there with any malicious intent.
"It was well handled by our people," Fairfield police Capt. John Zaban said.
But commuters were stuck after Metro-North trains were stopped from passing through the Fairfield area for three hours. And no foot traffic or cars were allowed to cross the bridge as investigators tried to determine whether there was any danger to the public.
One Fairfield commuter, Kevin Duffy, said he heard about the problem on the radio before he went to the station at about 7 a.m.
"You never know how long its going to take," Duffy said of the delay. He said he waits 45 minutes to an hour when there are train issues, and he had already reached his limit Friday morning.
MacNamara apologized to the commuters who were waiting outside the danger zone in the teacher parking lot of Tomlinson Middle School.
"Sorry for the inconvenience," he said to those gathered, but he said the police department will put public safety over convenience.
For most commuters waiting for the scene to clear, the biggest question was why the a bomb-sniffing dog from the Metropolitan Transportation Authority didn't go close to the suspicious box.
"The handler and the dog had to make assessments," MacNamara said. "And based on what the handler saw, he didn't want the dog to go closer."
Train delays of more than two hours were reported along Metro-North in Fairfield County and New Haven County. All three train stations in Fairfield were closed Friday morning during the incident.
Read more about the discovery of the box earlier Friday on the Daily Voice.
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