Des Plaines River Rescue: Sean O'Brien, Off-Duty Cop, Jumped Into Freezing River To Save 7-Year-Old

An off-duty Chicago-area police officer made a hero's rescue Tuesday afternoon rescuing a small boy who had sunk below the icy waters of the Des Plaines River.

Evanston police officer Sean O'Brien spotted the boy's Chicago Bears hat sinking in the river before the boy's hand popped through the ice, reports the Sun-Times. O'Brien jumped in to the waist-high water and pulled the 7-year-old to safety.

"He definitely saved the boy's life," Des Plaines Fire Chief Alan Wax told the Daily Herald. "(The boy) was only in the water a matter of seconds. The officer was able to go into the water up to his thighs and grab him."

O'Brien first spotted the boy alone near Miner Street and River Road in Des Plaines, Ill. around 3:40 p.m. Des Plaines Patch reports the O'Brien got out of his car and chased after the boy who had headed for the dam at Joseph Schwab Road.

"He picked up a chunk of snow the size of a football and took off running," O'Brien told the Sun-Times.

The child either jumped or fell into the icy water after throwing the snow in the river, and was taken to the hospital in good condition after the rescue. The boy's mother came to the hospital, but according to WGN, officials don't know why the boy was outside running around alone.

O'Brien, who the Sun-Times says was headed to the Blackhawks game after running errands, has made heroic rescues before.

According to a WGN broadcast (embedded), O'Brien, 26, rescued another officer from a fiery car crash in 2009.