Backed by acting Police Chief of Special Functions Steve Georgas, Chicago Marathon Race Director Carey Pinkowski says, "We're staying with the baseline we had in 2013" on security measures. View Full Caption DNAinfo/Ted Cox

WEST LOOP — Taking an "if it ain't broke, don't fix it" approach, the Chicago Marathon will impose many of the same security measures as last year on Sunday, according to city and race officials.

"We're staying with the baseline we had in 2013," Executive Race Director Carey Pinkowski said in a news conference Tuesday at the Office of Emergency Management and Communications.

Steve Georgas, the Chicago Police Department's acting chief of special functions, said the biggest concern is "a lone wolf" terrorist, on the order of the suburban Bolingbrook teen recently charged with attempting to join Islamic State fighters in Syria.

But, he added, "There are no credible threats to this event."

New security measures adopted last year in the wake of the Boston Marathon bombing, which Pinkowski called "enhancements" that were "extremely successful," will remain in place, including runners being asked to present a photo ID when picking up their race packets at McCormick Place on Friday and Saturday.

Runners are also asked to use the clear plastic bag included in the packet to store gear during the race, and will not be allowed to discard anything along the course for later pickup, as anything left behind will be confiscated.

The 1.7 million estimated spectators along the race course are again being discouraged from bringing backpacks, which will be subject to random searches from uniformed and plainclothes police officers along the route.

Only runners and ticketed spectators will be allowed near the start and finish lines in Grant Park as well.

Gary Schenkel, executive director of the Office of Emergency Management and Communications, advised spectators to "remain aware of your surroundings whenever at any high-profile event."

Director of Special Events David Kennedy said the 37th annual Chicago Marathon would attract runners from 132 countries, but marathon Medical Director Dr. George Chiampas said none were expected from the African nations struggling with an Ebola outbreak.

"Our runners are all coming from east Africa," Chiampas said.

Georgas added that there "is no direct threat" of Ebola, and Chicago Fire Department Assistant District Chief Mary Sheridan said the city had "plans to deal with any communicable disease."

"Those guidelines have not changed because of Ebola," Sheridan said.

Chiampas said people who have their cars towed from the race route Sunday morning should call 311, but that anyone reporting anything suspicious along the race course should call 911.

"Know the marathon route, know the closures and whenever possible take public transportation," Georgas advised.

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