OVERLAND PARK (REUTERS) - The suspect in the Passover Eve killings of three people at two Jewish community centres near Kansas City is a former Ku Klux Klan leader with history of spewing vitriol against Jews, law enforcement officials said on Monday.

Frazier Glenn Cross, 73, faces local and federal prosecution on hate crime charges after his arrest on Sunday for a shooting spree that killed a teenager and his grandfather outside a Jewish community centres, and a woman visiting her mother at a nearby Jewish retirement home.

Both facilities are in Overland Park, Kansas, an upscale suburb outside Kansas City, Missouri. It was a bitter irony noted by many in the area that none of the victims was Jewish. The boy and his grandfather were members of an area Methodist church and the woman attended a Catholic church.

Cross, of Aurora, Missouri, had a prior criminal history and was known by law enforcement and human rights groups as a former senior member of the KKK movement and someone who had long made public comments against Jewish people, according to the FBI.

"Yesterday's attack... strikes at the core fundamental freedoms... of how our country was founded and what we live by every single day," said FBI agent Michael Kaste.

"We've now determined that the motivation behind this was a hate crime. The acts that this person committed were the result of beliefs... that he had."

Johnson County District Attorney Steve Howe and United States Attorney for the District of Kansas Barry Grissom said they were collaborating on charges in local and federal courts.

Both the Southern Poverty Law Center, a leading anti-hate group, and the Institute for Research and Education on Human Rights (IREHR) have tracked Cross, who also goes by the name Frazier Glenn Miller, for years. The groups say he was involved in creating an armed paramilitary organisation in North Carolina 20 years ago.

The Southern Poverty Law Center said Cross is a "raging anti-Semite" who has posted online rantings that include "No Jews, Just Right". And the IREHR said he idolises Adolf Hitler.

"His worship for Hitler and Hitlerism is real," said Mr Leonard Zeskind, president of IREHR, in a statement issued on Monday.

The shootings started around 1pm at the Jewish Community Center of Greater Kansas City.

High school student Reat Griffin Underwood, 14, was with his grandfather, 69-year-old William Corporon, outside the Jewish Community Center when attacked. The teenager was at the centre to audition for a singing competition, according to family member Will Corporon.

The grandfather died at the scene and the boy died later at a hospital, police said.

The shooter then drove 1.6km away to the Village Shalom retirement community and fatally shot 53-year-old Terri LeManno, police said. LeManno was an occupational therapist and married mother of two children and was making a regular visit to her mother who lived at the retirement facility, police said.

It appeared the gunman had used a shotgun and possibly other firearms, police said.

Mr Kaste said the FBI had been aware of Cross and his background but was not monitoring him and had no warnings of the attacks. He said that it did not matter that the victims were not Jewish because hate crime violation are tied to the biases and beliefs of the suspect that motivate the crime, not the identities of the victims.

The FBI believes Cross acted alone, but is still investigating, Mr Kaste said.

President Barack Obama offered condolences and called the events "heartbreaking".