Three-time Olympian Jenny Simpson in hospital after collapsing at track event

• US runner reportedly lost pulse in medical incident

• Organizer thanks EMS and safety professionals

• Simpson won bronze in 1500m at 2016 Olympics

Jenny Simpson, a three-time Olympian and one of the most accomplished American female runners in history, was taken to hospital and is receiving treatment after collapsing at a track event on Tuesday in North Carolina.

The organizer of the event, Sir Walter Running, said there had been a medical incident" involving Simpson while she paced a mile group at an event in Raleigh. Runner's World and LetsRun reported that Simpson did not have a pulse for a period of time but said it was restored with CPR and an AED.