300 prospective jurors to be questioned ahead of Capital Gazette newspaper shooting trial

Five employees were killed at the Capital Gazette newspaper in June 2018.

Hundreds of prospective jurors are headed to a Maryland courthouse Friday as jury selection begins in the trial of the suspected Capital Gazette newspaper gunman.

On June 28, 2018, four journalists -- Wendi Winters, Rob Hiaasen, Gerald Fischman and John McNamara -- and a sales assistant -- Rebecca Smith -- were gunned down at The Capital Gazette newsroom in Annapolis in what became the largest killing of journalists in U.S. history.

The suspected gunman, Jarrod Ramos, allegedly had a long grudge against the newspaper.

Ramos, 39, facing charges including five counts of murder, has pleaded not criminally responsible -- Maryland's version of the insanity defense, reported The Capital Gazette.

Three hundred potential jurors will begin the selection process Friday, filling out questionnaires in one of the most high profile trial's in the area, according to Terri Charles, a spokesperson with the courts.

Three days of jury selection is expected to start on Oct. 30 with potential jurors coming to court in the morning and afternoon in batches of 50 at a time, said Charles.

The final jury selection will be on Nov. 4, said Charles.

ABC News' Dee Carden contributed to this report.