The FBI released a newly declassified document about the 9/11 attacks Saturday, revealing details about the logistical support given to two of the Saudi hijackers in the lead-up to the terrorist operation, as the world marked the 20th anniversary of one of America's darkest days. The 16-page document is the first investigative record to be shared since President Joe Biden ordered a declassification review of files about 9/11 last week. The document, which is heavily redacted, provides a summary of an FBI interview in 2015 with a man who had regular contact with Saudi nationals in the U.S. The man aided Nawaf al-Hazmi and Khalid al-Mihdhar, the first hijackers to arrive in the U.S., once they arrived in the country. Jim Kreindler, an attorney for victims' relatives, said in a statement that he believed "the findings and conclusions in this FBI investigation validate the arguments we have made in the litigation regarding the Saudi government's responsibility for the 9/11 attacks." He said that included Saudi officials' exchanging phone calls among themselves and with Al Qaeda operatives and then having "accidental meetings" with the hijackers while providing them with assistance to get settled and find flight schools. "This document, together with the public evidence gathered to date, provides a blueprint for how Al Qaeda operated inside the US with the active, knowing support of the Saudi government," he said.