Foursquare Founder Sorry for Wife Stealing Boston Marathon Bib Number

April 25, 2014— -- The founder of Foursquare issued a public apology today on behalf of his wife, who illicitly ran the Boston Marathon using another runner's official number.

Foursquare founder Dennis Crowley and his wife, Chelsa Crowley, ran the marathon together earlier this week after attempting to complete it together in 2013. But days later, another marathon runner accused Crowley of running the marathon as a "bandit," or someone who doesn't officially register to run or pay any fees.

Kathy Brown told ABC affiliate WCVB in Boston that she registered through the official channels and was running for a charity, which earned her a real bib number. After the race, she logged onto a photo website to see the pictures taken of her running.

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"I opened it up looking for the pictures of me and there were some in there and they came out really good, but then I saw this other woman," Brown told WCVB.

"It was pretty easy to figure out that someone just made a fake bib," said Brown.

With a little research, Brown found that Chelsa Crowley was one of those people. Crowley had put her Twitter handle on the bib, and had Tweeted about running as a bandit.

"I put that work in and it wasn't fair that someone else didn't have to do that. That was my first thought," said Brown.

Dennis Crowley wrote an apology on WCVB's website today after public outrage about his wife's theft. He linked back to a blog post he wrote before the marathon explaining why it was so important for his wife and him to run together.

According to the post on Medium, he and Chelsa were running the marathon together in 2013 but were separated before the bombs went off. Chelsa made it across the finish line moments before the first bomb exploded and Dennis was unable to get to the finish line, so he was allowed to run again automatically in 2014 but she was not.

"Yes, using a duplicate number to get Chelsa into the starting corral with me was wrong," Dennis wrote. "I don't expect everyone to understand our strong need to run and finish together -- but after trying unsuccessfully to get a charity number and trying unsuccessfully to officially transfer a number from an injured-runner friend, we did what we could to make sure we could run together in hopes of finishing together."

"I sent an email to Kathy Brown, the woman who rightfully earned #34033 to apologize for any disrespect, hurt feelings or confusion," he said. "Our intent was never to 'steal' anything from anyone -- our intent was to finish the Boston Marathon together as we tried to do last year."

"Again, sincerest apologies to anyone we offended or disrespected, including the [Boston Athletic Association] and the police/fire/EMT crews that worked so hard to make sure Monday's race was safe for all runners," he wrote and signed the letter on behalf of his wife.

Boston Marathon organizers said before the race that there would be a crackdown on bandits this year -- a major break with tradition at the event -- due to tighter security. They said they are now looking into multiple accounts of bandit runners.