Several hours after the shooting began, hostages started exiting the building and police declared the gunman dead.
By 1:30 p.m., police began escorting people out of the building, but continued to treat the building as a crime scene where the shooter might still be lurking.
The American Civic Association released a statement early Saturday morning.
"We are stricken with grief about today's horrific assault and share this grief with the victims' families, our community and the entire nation."
Eyewitness Nick Masucci, a community college student and Binghamton resident, said he watched as many as 20 people exit the building and get patted down by police.
"They look like immigrants, lots of different cultures coming out of there. Some people are getting patted down. The police are taking a lot of precautions, they're still taking cover," he said.
Several people were removed from the building on stretchers. Others left with their hands on their heads and were searched by police.
Earlier Friday, police called Broome Community College to find someone who could speak fluent Vietnamese to "assist police with translation," said college spokesman Richard David.
People were told in nearby buildings to stay away from windows and Binghamton High School is under a lockdown as police use the school as a staging area. The school is a block and a half away from the shooting site.
President Obama issued a statement from the NATO summit he was attending in France.
"Michelle and I were shocked and deeply saddened to learn about the act of senseless violence in Binghamton, N.Y., today. Our thoughts and prayers go out to the victims, their families and the people of Binghamton," he said.
New York Gov. David Paterson called the shooting "the worst tragedy and senseless crime in the history of the city."
"We all just have profound sorrow and sadness," he said.
Additonal reporting by ABC News' Ned Potter and Ki Mae Heussner, as did the Associated Press.