The Barley Saturday horse pictured on his escape from Cardigan parade

Shock can be seen on the faces of spectators lining the streets for the iconic event.

The equine parade was at the top of High Street and had nearly reached its conclusion when the grey horse was seen to 'hurl' his handler to the ground, according to one witness.

The horse begins his 'thundering' run. (Image: Gareth Davies Photography)

“The horse looked completely out of control and kept on running at a ridiculous speed, twice as fast as it would normally go," he said.

Another spectator standing further up the road recounted what he saw as the horse galloped up the street at a 'thundering' pace.

The horse made off at a 'ridiculous' speed, said one spectator. (Image: Gareth Davies Photography)

“People in the parade started shouting to those ahead, but one woman – I think she was handling a donkey – couldn’t have heard," he said.

“The next thing we knew, she went down like a sack of spuds.

“I was so shocked that I swore out loud, and I actually feared for the worst.”

All eyes were on the horse as he galloped on his way. (Image: Gareth Davies Photography)

The parade was temporarily halted while police who were on duty at the event rushed to the scene, together with a St John Ambulance and a Wales NHS ambulance.

“There was a general hubbub of shock amongst the crowd when it happened, and then an appalling silence,” continued the witness.

The lone runner..... (Image: Gareth Davies Photography)

“The NHS ambulance left the scene about 3.30pm but there are unconfirmed reports that the person was ‘walking wounded,” he added.

Dyfed-Powys Police, the Wales Ambulance Service and the Barley Saturday parade organisers have been contacted for further information.