At least 500,000 men -- and possibly more than a million -- are expected to attend next month's Promise Keepers prayer meeting on the National Mall, city officials said Thursday.
A crowd of such magnitude would rank the Oct. 4 gathering among the largest events in the capital's history.
"We see at least a half-million, and it may be going over a million," said Samuel H. Jordan, head of the District of Columbia's Office of Emergency Preparedness. "This city will be inundated with people."
Jordan invited reporters to a briefing on the logistics of the event and steps being taken to ensure security, adequate transportation, communications and health and safety.
Officials predicted that space will need to be found for more than 5,000 buses and said that as of Wednesday 4,100 buses had registered.