Kansas, US (BBN)-A 73-year-old white supremacist shouting “heil Hitler” killed three people Sunday — including a 14-year-old boy and his grandfather — during a shooting rampage at a Jewish center outside Kansas City, Kansas, police said.

Witnesses said the sicko singled out Jewish victims, reports nydailynews.com.

“Asking someone if you are Jewish before shooting sounds very much like a hate crime,” Rabbi Herbert Mandl, a chaplain with the Overland Park, Kan., Police Department, told CNN.

Police Chief John Douglas said the Passover eve attacks happened at the Jewish Community Campus of Greater Kansas City and at the nearby Village Shalom senior living facility.

The gunman, identified by the Kansas City Star as Frazier Glenn Cross of Aurora, Mo, was arrested following the explosion of violence in the community 11 miles south of Kansas City.

My family is Methodist. Whatever weird psycho hatred Cross has against people who are Jewish — and they weren’t even Jewish.

Cross, who also goes by the name Frazier Glenn Miller, is founder of the now-defunct White Patriot Party, a Ku Klux Klan group that was based in North Carolina, according to the Southern Poverty Law Center.

Witnesses said Cross screamed “heil Hitler” and smirked as he opened fire with a shotgun about 1:00pm outside the community center.

Dr William Lewis Corporon, 69, was taking his 14-year-old grandson Reat Griffin Underwood to an American Idol-style talent competition at the center when they were “ambushed” by the gunman, Corporon’s son Will told the Daily News.

The grandfather and grandson were in the car and had just pulled into the parking lot when they were shot, said Will Corporon, 49, who lost his father and nephew in the senseless killing.

Dr William Lewis Corporon, 69, and his grandson, Reat Griffin Underwood, 14, two of the three people killed in attacks at Jewish-affiliated facilities near Kansas City, Kan.

“He was taking him to this audition and as soon as they got in the parking lot, this guy ambushed them and killed them,” said a heartbroken Will Corporon.

“It’s the ultimate irony. My family is Methodist. Whatever weird psycho hatred Cross has against people who are Jewish — and they weren’t even Jewish.”

The family patriarch leaves behind a wife of 49 years, three grown children and 10 grandchildren, while Reat leaves a younger brother, Will Corporon said.

At the time of the shooting, young people were gathering at the center’s theater to rehearse a production of “To Kill a Mockingbird,” which Corporon said was part of the talent contest.

“There were tons of kids because this was about to start at 1 o’clock,” Ruth Bigus, spokeswoman for the theater group, told the Kansas City Star.

The suspect reportedly yelled 'heil Hitler!' as he opened fire at the community center.

After shooting Corporon and Reat, Cross then went to Village Shalom senior living facility, where he shot and killed an unidentified elderly woman, police said.

Cops arrested the gunman outside a nearby elementary school. The man spewed anti-Semitic slurs as officers led him away, the Kansas City Star reported.

The killings sent shock waves all the way to the White House and New York, where security was increased at synagogues.

“The NYPD is taking all steps to ensure the safety and security of Jewish individuals and institutions as Passover is being ushered in,” Mayor de Blasio said in a statement.

A Kansas State Trooper stands near the location of a shooting on Sunday at the Jewish Community Center in Overland Park, Kan.

President Obama said, “While we do not know all of the details surrounding today’s shooting, the initial reports are heartbreaking."

BBN/ANS/AD/14Apr14-1:10 pm (BST)