Two bike messengers saved the day for a Los Angeles man Monday when they chased a bike thief for five blocks downtown and then knocked him to the ground, causing him to flee, police said.

Jesus Tobar, 43, said he was working out at 24-Hour Fitness in the 500 block of Flower Street in downtown Los Angeles when he emerged to find his green Iron Horse Desperado Mountain Bike gone.

Tobar returned to the gym to ask if there was any security surveillance video. But two bike couriers had seen his $500 bike being taken and had already set off after the thief.

The couriers pedaled through downtown at high speed on a chase that traversed sidewalks and busy streets, said LAPD Cmdr. Andrew Smith. Eventually, one of the messengers was able to grab the thief's shirt and pull him to the ground.

The man then took off on foot and the couriers reclaimed the bike.

"This was a wild, high-speed bicycle chase through crowded streets of the Jewelry Mart," Smith said. "We are now looking for a 30-year-old man with a torn shirt, a possibly sprained ankle, as well as road rash."