Four people were found dead inside a home shortly before a shooting nearby that left three in hospital.
The incidents, which police believe are connected, happened in Bowdoin and Yarmouth, Maine.
Maine State Police Lt. Randall Keaten told reporters during a press conference: “We’re working many different scenes. We’re just getting our arms around it.”
Shortly after finding the four bodies, shot to death, at the Bowdoin home police got reports of vehicles being shot at on a major road nearby.
A vehicle within the crime scene on the I-295 appeared to be riddled with multiple bullet holes.
One of those injured there is in critical condition.
Police closed the I-295 going southbound while police searched for a suspect.
One suspect was detained by police, but a search for a possible second suspect continued “out of an abundance of caution,” a spokesperson for the Maine State Police said.
The suspect detained by police is reportedly being interviewed, though police have not yet confirmed where. They did confirm that the person is not among those hospitalised.
Police have since said there is no threat to the public "right now".
"As a result of the shootings, four people were found deceased inside a home on the Augusta Road in Bowdoin," police said. "A short time later at approximately 10,30 am, three people were shot while driving their vehicles southbound near Mile Marker 17 and Exit 15 in Yarmouth."
"Both shootings are connected," Maine State Police said. "Investigators are currently working these scenes and will result in the road closure of I-295 southbound at Mile Marker 20 in Freeport to the Exit 15 off-ramp in Yarmouth for an undetermined amount of time."
Neither the victims nor the suspect arrested have been identified.
The police said there are cars "all over" who had been hit by stray gunfire.
An eye witness told WMTWTV: "All I saw was just gun smoke like something out the end of a barrel coming from the vehicles.
"You could see it going into the passenger lane and you could see gunsmoke going into the driver lane. Then multiple vehicles just started swerving around. Then three of them pulled over to the side at the same time."
At this stage the motive behind the shooting is unclear.
Lisa Erickson, who lives near the second scene, said she heard gunshots from her home.
Within moments, police officers arrived in the area and shouted for her and her neighbours to stay in their homes.
She told Sun Journal: “This is crazy. “This is Yarmouth, Maine.”
Police have asked anyone who saw the incidents to get in touch with the police.
Investigations continue.
