In the aftermath of the Boston Marathon bombings, the Bank of America Chicago Marathon is imposing beefed-up security measures for the 26.2-mile race Oct. 13.

"The bag check is something we've been looking at for a couple of years," Carey Pinkowski, the event director, said Thursday. "Is it something that's in response to Boston? I would think partly … but it's something that had been on our radar for a long time."

Marathon participants will be allowed to bring only a 24.5-inch-by-17.5-inch clear plastic drawstring bag issued to them for the event. Any bags left unattended during the marathon will be "collected and discarded," according to a news release. Runners will have a chance to check their event-issued bags before starting the race.

Race organizers and city officials said they notified the 45,000 participants.

In the April 15 Boston Marathon tragedy, pressure cooker bombs hidden in backpacks exploded near the finish line, killing three people and injuring more than 260.

Chicago Marathon spectators are technically allowed to bring bags to the reunion area at Grant Park's Butler Field but are strongly discouraged from doing so "to maintain an efficient flow of pedestrians," according to a marathon news release. As in the past, spectators will not be able to congregate at the start of the race or the finish line, but they can gather elsewhere on the route. Spectator bags along the race's course will be subject to random searches throughout the event, and Chicago police will have bomb-sniffing dogs at the race, according to the city's Office of Emergency Management and Communications.

As an additional security measure this year, participants will have to present identification to pick up their race packets — no one can pick up a packet on someone's behalf. Participants will enter the race through designated gateways on Jackson Drive, Congress Parkway and Harrison Street off of Michigan Avenue.

Chicago Marathon spokesman Jeremy Borling said the city already had employed some of the new security measures for Lollapalooza and the Blackhawks' victory parade.

The Chicago Marathon typically attracts runners from all 50 states and more than 100 countries and more than 1 million spectators.

"It's going to simplify the process," Pinkowski said. "But getting into the start area, the fact that we're using those clear bags that can be screened quickly, our guys can work efficiently and effectively. ... When a person finishes a race, (on) a cool day they want to get into some dry material — it's a big enough bag that they can put some clothes (in it) and get in some dry clothes."

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