DOWNTOWN — Police will have 1,000 additional officers — many undercover — patrolling the route of the 40th annual Chicago Marathon, officials said Thursday — hours after revelations that the gunman who opened fire on a music festival in Las Vegas booked rooms at a Michigan Avenue hotel across the street from this summer's Lollapalooza.
"There has been a double- and triple-checking of everything" involving marathon security, Mayor Rahm Emanuel said at an event designed to kick off four days of marathon-related events.
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Flanked by Chicago Police Department officials and the head of the FBI's Chicago office, Emanuel said the marathon would "go forward correctly."
"We are going to show what we are made of," Emanuel said. "This is what the City of Chicago does. We are the city of big shoulders. We put on big events. We host 'em, and people enjoy 'em."
Emanuel said he was "absolutely, 100 percent" confident that city officials had taken the steps to prevent an attack from an elevated position along the 26.1-mile route of the race.
City officials — led by Alicia Tate-Nadeau, executive director of Chicago's Office of Emergency Management — reviewed the city's contingency plans in the event of an attack from an elevated position along the marathon route after the mass shooting in Las Vegas killed 58 people and injured 489.
City officials met Thur tsday with hotel security forces to educate them on the threat, Tate-Nadeau said, declining to discuss tactics that will be used.
"We do have a very robust plan in place," Tate-Nadeau said.
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Anthony Riccio, chief of the Police Department's Bureau of Organized Crime, said the city had learned from previous attacks — including what happened in Las Vegas — and a "significantly larger number of undercover officers" will be assigned to mingle with the crowd on the route and at the start and finish lines among the runners.
Spectators who see something that alarms them should call 911, Riccio said.
Emanuel's son, Zach, will run the marathon to raise money for the victims of Hurricane Maria in Puerto Rico.
"I am immensely proud of my son," Emanuel said.
