Geert Vanden Wijngaert/Associated Press

Independent marathon-running investigators are not to be trifled with.

Earlier this week, business analyst Derek Murphy caught Jane Seo, a 24-year-old Huffington Post writer, red-handed after she placed second in the Fort Lauderdale A1A Half Marathon.

Murphy went all-in. He studied distance trackers, maps, heart-rate monitors and even Seo's race photos. From Sam Machkovech of Ars Technica:

"Murphy began poking around official photos from the event and found one of Seo smiling with a second-place award around her neck—and a clearly visible Garmin 235 screen on her wrist. He paid for a higher-resolution version of the photos, and they showed a running-distance tally on the wrist hardware's screen: 11.65 miles. Even factoring in a margin of error, that measure is well short of a half marathon's 13.1 mile total."

Murphy also pointed out that Seo got faster as the race wore on, which is highly unusual in long-distance running. She averaged a 7:09 mile for her first 10 kilometers and a 5:25 for her remaining about 11 kilometers.

Seo tried to cover her tracks by biking over the course later on and posting her "run" to Strava, a social network for bicyclists and runners.

"Had she just admitted what she did, I never would have heard of her, nor written about her," Murphy told Nick Sortal of the Miami New Times. "But going back and biking the course to cover up ... that's unheard of."

Seo posted an apology admitting to the cheating on Instagram but later deleted it. Murphy screen-grabbed it and posted it on his site, MarathonInvestigation.com.

[h/t Ars Technica]