FEMA also interfered in the Astor Hotel's' plans to hire 10 buses to carry approximately 500 guests to higher ground. Federal officials commandeered the buses, and told the guests to join thousands of other evacuees at the Ernest N. Morial Convention Center. In other instances of FEMA asserting its authority to only ultimately make things worse, FEMA officials turned away three Wal-Mart trailer trucks loaded with water, prevented the Coast Guard from delivering 1,000 gallons of diesel fuel, and on Saturday they cut the Jefferson Parish emergency communications line, leading the sheriff to restore it and post armed guards to protect it from FEMA. The Wal-Mart delivery had actually been turned away a week earlier, on Sunday, August 28, before the hurricane struck. A caravan of 13 Wal-Mart tractor trailers was reported in New Orleans by September 1. Additionally, more than 50 civilian aircraft responding to separate requests for evacuations from hospitals and other agencies swarmed to the area a day after Katrina hit, but FEMA blocked their efforts. Aircraft operators complained that FEMA waved off a number of evacuation attempts, saying the rescuers were not authorized. "Many planes and helicopters simply sat idle," said Thomas Judge, president of the Assn. of Air Medical Services.