Two US firefighters have been shot dead and two others wounded when a gunman opened fire as they responded to a Christmas Eve blaze, in what police are calling an apparent ambush.
Gunman kills two firefighters in upstate New York
A gunman kills two firefighters who were responding to a house fire in Webster, New York. Two more are injured in the shootout.
The incident - which comes as debate rages in the United States about gun control following the Newtown school massacre earlier this month - happened shortly before 6am (10pm AEDT) on Monday in Webster, on the shores of Lake Ontario in New York state.
The shooter was found dead at the scene, apparently of a gunshot wound. Police have not speculated on a possible motive.
"It does appear that it was a trap that was set for our first responders," Webster police chief Gerald Pickering told a news conference, adding that investigators were pursuing several leads.
"The responding firefighters, when they pulled up at the scene, were fired upon," Pickering said.
"Four of the firefighters were shot. Two are deceased, two were transported to area hospitals," he added, noting that the two injured were in a serious condition.
"We are a safe community, a tragedy like this is just horrendous."
Pickering said it appeared there was only one shooter, and the suspect was found dead, apparently by a gunshot wound. It was not immediately clear if he killed himself or was shot in the crossfire with police.
"There was some pursuit ... the threat has been eliminated," he said. "The neighbourhood is safe at this time."
A security cordon was put up around the scene and residents were evacuated. Firefighters were still battling to contain the blaze, as the shooting thwarted initial efforts to douse the flames.
So far, four homes have been destroyed and four others damaged.
New York state governor Andrew Cuomo called the incident a "horrific shooting" and offered his condolences to the families of the victims.
The incident in Webster comes 10 days after the shooting rampage at an elementary school in Newtown, Connecticut, in which 20 children, aged six and seven, and six adults were killed.
The shooter, Adam Lanza, killed his mother at their home before heading to the school, where he eventually took his own life.
The Newtown shooting has revived debate in the United States on the country's gun laws, which are far more lax than in most other developed nations.
President Barack Obama said he would support a new bill to ban assault rifles, and has put Vice-President Joe Biden in charge of a panel looking at a wide range of other measures, from school security to mental health.
Democratic Senator Dianne Feinstein has pledged to introduce a bill in January that would ban at least 100 military-style semi-automatic assault weapons, and would curb the transfer, importation and the possession of such arms.
But the nation's most powerful gun lobby, the National Rifle Association, strongly opposes any new restraints in gun sales, with the group's executive vice-president Wayne LaPierre calling Feinstein's proposal "phoney'.