Three people, including a pregnant woman and a young boy, have been shot dead in a horrific attack in southern Spain.

A fourth person was left fighting for their life following the shooting in Isla Cristina, Huelva, on Sunday evening.

The attack took place on Calle Valverde del Camino in the town’s El Rocio neighbourhood, when two men in balaclavas pulled up on a motorbike, before one opened fire.

Footage shared online showed the three bodies sprawled out on the pavement as residents gathered nearby.

Men can be seen casually walking past the corpse of a young boy as a pool of blood begins to gather around him.

The dead are understood to be a pregnant woman, one of her children and the woman’s mother. Their bodies were left in the street following the attack.

A fourth person suffered extremely serious injuries and was being treated by emergency medics.

Investigators are examining whether the bloodshed could be linked to an ongoing feud between two families.

The victims are reportedly relatives of a person accused of killing a man in the Torrejon neighbourhood of Huelva city on September 10.

Several violent incidents involving members of the two families are said to have followed that killing, including a recent shooting at the same location in Isla Cristina.

Police are therefore investigating revenge as one possible motive, although the circumstances have yet to be established.

Numerous Guardia Civil and Local Police officers were deployed to the scene on Sunday night, while investigators launched a search for the suspected gunman.

The area remained under a heavy police presence as the investigation continued.

Read more Andalucia news at the Spanish Eye.