BOSTON (CBS) — This year’s Boston Marathon runners are being warned against putting their bib numbers on social media before the race.

In 2014, a handful of runners who did not qualify used photos found on social media to duplicate bibs and join the race.

The Boston Athletic Association is hoping to avoid that this year with some new instructions in their handbook.

“The B.A.A. asks participants not to post close-up pictures of their bib number on social media before the race to avoid fraudulent bib duplication,” the rules state. “The B.A.A. will disqualify anyone found to have duplicated a bib number, or been the source of a duplicated bib number.”

The B.A.A.’s Executive Director Tom Grilk tells WBZ NewsRadio 1030 that while there were very few duplicate bibs last year, the violation is a serious one.

“It presents a very legitimate security anxiety for everyone who is both watching the race and in the race,” he said.

Last year, runner Kara Bonneau of North Carolina found that her bib had been duplicated by four other people when she checked the website after the race.

“There were dozens of pictures of these other people,” she told WBZ at the time. “When I looked at them, they had my corral number, 2014, and then I realized it must have been from the picture that I posted on the web.”

She said she felt bad for friends who ran qualifying times, but could not get in when race officials closed the field.

“There were people there who had no right to be there,” Bonneau said. “It was awful that someone would do that without going through any of the work that the rest of us had put in to get there.”

WBZ NewsRadio 1030’s Lana Jones reports:

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