New York State trooper shot dead had 'his whole life before him': Governor Nicholas Clark, 29, was shot while responding to a suicidal person report.

A young New York State Police trooper with "his whole life before him" was gunned down early Monday while responding to a report of a suicidal person barricaded inside a home, the governor said.

When Trooper Nicholas Clark responded to the call at about 3:30 a.m., Steven Kiley shot and killed him, the New York State Police said.

Kiley, 43, was later found dead from an apparent gunshot wound inside the home in Steuben County, near the Pennsylvania state line, police said.

Clark, 29, of Troupsburg, New York, is survived by his mother, father and brother, police said.

"To the Clark family, to his mother, his father, his brother, we hope you find peace in this senseless act of violence," Gov. Andrew Cuomo said at a news conference Monday. "A 29-year-old trooper, a stellar trooper with an extraordinary record, his whole life before him. Great athlete. Well accomplished. He wanted to do one thing -- which was help people."

"This is one situation that I've gone through before," Cuomo continued. "Thirteen troopers lost in five years. There's no answer. There's no point. It's just sad and painful."

Every day is dangerous for police, Cuomo said, from domestic violence incidents to storms to potential terrorism.

"To the state police and to all police officers in this state," Cuomo said, "I want them to know that every person in the state of New York has nothing but respect for them, trust in them, and love for them and their families."

"We know the danger that you put yourself in every day when you leave the house," the governor said. "We know the fear that is in your families' heart when you're out there. And we truly and deeply appreciate the risk that you take to keep our families safe."

Flags on all state government buildings will be flown at half-staff, Cuomo said.

New York Lt. Gov. Kathy Hochul, New York Sen. Chuck Schumer and New York Attorney General Barbara Underwood were among those who offered their condolences on Twitter.

ABC News' Aaron Katersky contributed to this report.