19 April 2012 Last updated at 12:15 ET

Texas cockfight shooting kills three and wounds eight

The cockfight took place in a rural area of southern Texas, reachable by dirt road (file pic)

Masked gunmen opened fire at an illegal cockfight, leaving three dead and eight wounded at a ranch in rural southern Texas, police say.

Spectators trampled the victims and evidence as they ran, Hidalgo County Sheriff Lupe Trevino said, describing the site as "a crime scene from hell".

Others scattered into the brush and some managed to leave by car, local news channel KRGV reported.

Officials are looking for suspects, the sheriff's office said.

Investigators do not know what prompted the shootings, the sheriff's dispatcher told the Associated Press news agency.

But officials were combing through beer cans and cups near a low building with a corrugated metal roof fitted with metal stands, where the cockfights took place.

"A lot of spectators trampled all over the spent casings, trampled the victims. The whole crime scene was in disarray. Everything has been contaminated," Mr Trevino told KRGV.

"We just have to comb through all that stuff to figure out if there's any evidence we can use."

The sheriff added that nothing appeared to have been taken from the scene, and sheriffs deputies were questioning the property owners.

The ranch, located close to the US border with Mexico, is accessible by dirt road running past a "no trespass" sign.

In the wake of the shooting one car caught fire, reports said, but officers helped the passengers get to hospital.

The condition of those wounded is not known. So far, no arrests have been made.

During cockfights, the birds are fitted with sharp metal blades or curved spikes on their legs.

They battle till one or both of the birds dies or is maimed, while spectators gamble on the outcome of the match. Cockfighting is illegal in Texas.