A major focus of the search for Robert Card, the man suspected of killing 18 people in Lewiston, Maine, on Wednesday night, is a bend of the Androscoggin River in nearby Lisbon.
Authorities on Friday shared a map of the area, where law enforcement was seen all day searching by land, water and air. They also shared detailed aerial maps of the two shooting scenes: Just-In-Time Recreation, a bowling alley on Mollison Street, and Schemengees Bar and Grille restaurant on Lincoln Street, about four miles away.
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Card's white Subaru station wagon was found Wednesday night at Paper Mills Trail and Miller Park Boat Launch on Frost Hill Avenue, Maine State Police said, and an intensive search of the river around the area was begun.
Helicopters were seen flying low over the river. Maine Department of Public Safety Commissioner Michael Sauschuck said Friday morning that they were being used to determine "what can we clear from the air … can I tell from the top, based on the current and how muddy the water is, can I see all the way to the bottom?"
Divers were also in the water — which was lower than usual, after authorities requested that a local hydropower company use its dam to decrease the current downriver.
"If we can slow that current down, we can lower the amount of water in the river — it's certainly easier for us to work," Sauschuck said.
On the shore, law enforcement on foot was line-searching on land — while heavily armed officers in Durham, across the river, were seen conducting a search. Authorities later said they flooded the area when a sheriff's deputy didn't respond to radio calls after checking a building where two 911 hang-up calls had come from.
Sauschuck said a search by land was planned for Moore's Island, in the middle of the river, as well.
Much of the river search was aimed at finding Card's body, in case he's dead. While that search was going on, another team of law enforcement agents was searching the area under the assumption he's still at large — he's been considered armed and dangerous.
"Clearly we don't have him located at this point, we don't have him in custody. So all of those options are on the table," Sauschuck said at the news conference.
Meantime, crews were still combing through the areas in and around the bowling alley and restaurant in Lewiston for more evidence, Sauschuck said. He expected it would be days before that work would be completed.
Wednesday's shootings — the deadliest in Maine history, according to Sen. Susan Collins, R-Maine — have left the community reeling, but lockdowns remained in place for a large swath of central Maine while Card was unaccounted for.
Officials rescinded a days-long shelter-in-place order Friday night.
More on the Lewiston, Maine, mass shootings
Investigators have received more than 530 tips and leads, and they've set up an FBI tip line for more: fbi.gov/lewistontips. Sauschuck also confirmed that a note was found at Card's home in Bowdoin, as NBC New York reported Thursday, but didn't share information about what was in the note, citing the ongoing investigation.
