A man accused of fatally shooting three people at Jewish sites in Kansas declared "Heil Hitler!" and asked how many Jews he had killed after the attacks, a police officer who was at the scene testified Monday.

Frazier Glenn Miller, 74, is charged with capital murder in the April 13, 2014, shootings at the Jewish Community Center of Greater Kansas City in Overland Park, Kansas, and at a nearby Jewish retirement home. None of the victims was Jewish.

Overland Park police Sgt. Marty C. Ingram testified Monday at a preliminary hearing to determine if there is enough evidence to put Miller, of Aurora, Missouri, on trial. Prosecutors plan to seek the death penalty.

Ingram said he heard shots fired at the Jewish Community Center and saw the doors of the center's theater shatter. He said he took cover as more shots hit the building's facade.

"Dust, smoke was flying everywhere at that point," he said. The gunman then drove away.

When he heard that fellow officers had arrested a suspect, Ingram accompanied some witnesses to the arrest scene to determine if they could identify him. As they approached the patrol car where Miller was detained, he shouted "Heil Hitler!" and asked how many Jews he had killed.

Miller is accused of killing Dr. William Lewis Corporon, 69, and his 14-year-old grandson, Reat Griffin Underwood, who were attending a singing contest audition at the Jewish Community Center. He also is accused of killing 53-year-old Terri LaManno, who was visiting her mother at a nearby Jewish retirement home.

At a December hearing, Miller, who has emphysema, said he was afraid that he doesn't have much time left to live following a trip to the emergency room in March. In several phone calls to The Associated Press, Miller said he thought he was dying and felt he was fulfilling a patriotic duty by killing Jews. He regretted shooting the teenager, who he said looked older.

Miller, also known as Frazier Glenn Cross, is a Vietnam War veteran from southwest Missouri who founded the Carolina Knights of the Ku Klux Klan in his native North Carolina and later the White Patriot Party.

After a nationwide manhunt in 1987, federal agents found him and three other men at a rural Missouri home stocked with hand grenades and automatic weapons. Miller was indicted on weapons charges and accused of plotting robberies and the assassination of the Southern Poverty Law Center's founder. He served three years in federal prison.

Miller also ran for the U.S. House in 2006 and the U.S. Senate in 2010 in Missouri, each time espousing a white-power platform.