The eight suspects, seven men and one woman, aged 17 to 22, made their initial court appearances on Monday. Six of them face federal gun charges.

It was from the sixth floor window of the Texas School Book Depository — now called the Dallas County Administration Building — that Lee Harvey Oswald took aim and killed President John F. Kennedy on November 22, 1963. President Kennedy was riding in a motorcade through Dealey Plaza in downtown Dallas, Texas when he was struck.

The operation focused on distribution of illegal machine gun conversion devices, or “switches,” which can turn semiautomatic firearms into fully-automatic guns, officials said.