The wounded firefighters were in intensive care Monday at Strong Memorial Hospital in Rochester, New York, officials said.
The other person wounded was a Greece, New York, police officer who was on his way to work when his car was fired upon. He suffered shrapnel wounds that Pickering described as minor.
"We work with these people everyday; they're like our brothers," said Pickering of the slain firefighters, as he fought back tears. "It's terrible."
New shooting spurs more talk on gun control
Authorities have not said what weapons were found with Spengler, though Pickering said "probably at least a rifle was used" to shoot the first responders.
"I know that many people are going to be asking, 'Were they assault rifles?' I don't know that. I can't answer that at this time," he told reporters.
The shooting occurred amid a renewed gun control debate after the December 14 elementary school massacre in Newtown, Connecticut, that killed 26 people, most of them children. The gunman in that case, Adam Lanza, also killed his mother and himself.
The head of a lobbying group that represents first responders said the Monday shooting was "senseless and cruel."
"The firefighters who responded today were performing a selfless, meaningful service to their community, unaware that a cold-hearted maniac was planning to ambush them and take their lives," said Harold Schaitberger, general president of the Washington-based International Association of Fire Fighters. "Coming on the heels of the horrific tragedy in Newtown, Connecticut, and on Christmas Eve, this shooting is even harder to comprehend."
New York Gov. Andrew Cuomo described the Webster shooting as "horrific." And the state's attorney general called it a "senseless tragedy"
President Barack Obama has set a January deadline for "concrete proposals" to deal with gun violence in the wake of the Newtown school shooting.
Sen. Dianne Feinstein, D-California, has said she will introduce legislation to reinstate the assault weapons ban that expired in 2004, while National Rifle Association CEO Wayne LaPierre has said his group will fight any new gun restrictions, saying most gun laws now on the books are rarely enforced.
Pickering, the Webster police chief, said it was important -- in the wake of the shooting in his town and others -- to "get a handle on gun control." He also said more needs to be done to make sure that dangerous people aren't in society, where they can kill.
"For the last 20 years we have been turning people loose and deinstitutionalizing people, and I think we've swung too far," he said. "I think there are still people that need to be in institutions that are a danger to themselves or others. And this is a classic example."