This is the moment people run for cover shortly as an explosion from a hand grenade rocks the public stands of a cockfighting event.

CCTV footage of the event shows contestants in the ring with their roosters getting ready for a bout in Epazoyucan, Mexico on 26th December.

But moments before the fight, an explosion can be heard coming from the spectators’ seating area.

As people scramble to flee, one owner can be seen trying to scoop up both his birds as he runs for cover.

Police said the crowd started to run after two objects were thrown into the seating area.

They later identified these as homemade grenades which slightly injured several people.

Only one of the two DIY grenades went off, they added.

Medics called to the arena to treat the injured and also treated other spectators for shock.

Police say they are looking at who was behind the incident and have made no further statement.

In Mexico, cockfighting is legal in some parts of the country where it is not only mainstream but also often organised alongside musical events to entertain the public.