Bikers hoping to cruise nonstop through Washington, D.C., on Wednesday, Sept. 11 received disappointing news over the weekend: the city denied their permit request.

"We find this regretful for the residents and businesses of that great city, and humbly offer our apologies," organizers of the ride said Friday on Facebook. "What could have been a one or two hour ride through will now likely be an all day event."

It's legal for motorcycles to drive through D.C. and participants plan to cross into the capital undeterred after 11 a.m. "For security purposes the final route will not be posted publicly," the organizers added.

It's unclear if law enforcement will take action against what may be a traffic-clogging permitless demonstration on wheels.

Riders plan to abide by all relevant traffic laws, such as yielding to pedestrians and stopping at red lights.

But a member of the D.C. police department's public affairs office told U.S. News officers will act "if there is a crime committed."

It would be a crime for riders to engage in certain activities "if a permit is required" for them, according to the police spokesman.

"2 MILLION BIKERS TO DC" The State of Maine, Chapter had kickstands up yesterday. Heading to D.C.#2MBikers pic.twitter.com/gI41I40Ka1 — HangEmHigh (@HangEmHigh69) September 9, 2013

The Muslim-initiated demonstration received a permit from the National Park Service for use of the National Mall. Its participants will include groups that doubt the official account of the 2001 terror attacks, at least one tea party organization, Princeton professor Cornel West and Congressional Black Caucus Chairman Rep. Emanuel Cleaver, D-Mo.

Bike riders are already en route from across the country. Local press reports said bikers whizzed through Florida and Texas Sunday on their way to D.C. Photos posted to Twitter show meetups in Phoenix, Knoxville, Tenn., and Maine. Organizers set up Facebook groups to help organize participants from each of the 49 continental states.

Ted Gest, a spokesman for the D.C. attorney general's office, which would prosecute alleged infractions, did not immediately respond to a request for comment.