State police have not identified them. They said an autopsy is scheduled.
They provided an update on the Quinnipiac Avenue situation on Thursday morning.
"This is an active investigation," said Trooper Kelly Grant, Connecticut State Police. "Obviously a lot of fire damage, so there is going to be a lot of collecting evidence and sifting through and seeing what we have out there."
Troopers said a man held his wife hostage inside of a home on Quinnipiac Avenue for several days.
She escaped and alerted police, but he barricaded himself inside a barn near a house on the property.
That's where police said the explosion happened on Wednesday night.
Nine officers were taken to Yale-New Haven Hospital. All of the patients were listed in fair condition as of Thursday morning.
Troopers would only confirm that suspect was not in custody.
"They have asked the residents right in this general vicinity to shelter in place while they conducted this investigation," Grant said.
The shelter in place order remained in place for neighbors.
The area surrounding the property was blocked off by rows of cruisers. Quinnipiac Avenue was closed between McArthur Road and Pentway Lane.
School buses were reportedly affected by the investigation, according to M&J Bus Company. Two buses had to be rerouted on Thursday morning.
North Haven police said they first responded to the scene around 2 p.m. on Wednesday.
When they arrived, the man had barricaded himself in the barn.
Troopers told Channel 3 that they determined a tactical response was necessary.
"Our detectives began an investigation [Wednesday] afternoon and as it progressed we determined there was a need for a SWAT team," said Deputy Chief Jonathan Mulhern, North Haven Police Department.
While police and the SWAT team were negotiating with the man, state police said there was an explosion at the barn.
Flames were captured in video that was recorded at the scene.
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