An abattoir in Australia has been investigated for animal cruelty after secretly recorded footage appeared to show chickens being boiled alive during the slaughter process.

The Star Poultry Supply slaughterhouse in the Melbourne suburb of Keysborough was criticised for the "extremely horrific" footage, which appeared to show hens being dipped into scalding hot water while still alive

The footage, broadcast by ABC's 7.30 program, was obtained by animal rights activists who secretly set up cameras inside the abattoir to film the apparent abuse.

The egg-laying hens at the factory are slaughtered when they are "spent", aged just 18 months. During the process, the animals are stunned before their throats are slit.

They are then plunged into boiling water to remove their feathers. However, the footage shows some chickens are still alive before being forced into the water.

One of the campaigners, Tamara Kenneally, told 7.30: "They were actually going through the conveyor on the shackles alive, and being dunked into the boiling water alive. So they were being scalded to death basically."

The footage was later passed onto Victoria's abattoir regulator, PrimeSafe, for investigation. They then referred it to Agriculture Victoria, the department responsible for enforcing the state's animal cruelty laws.

Agriculture Victoria said they spoke to those working at the abattoir, but did not launch a full investigation into the alleged animal cruelty.

A spokesperson said: "Agriculture Victoria was satisfied that the remedial action being taken by the company, at the direction of PrimeSafe, and some staff changes would help manage the instances of poor practices demonstrated on the footage."

RSPCA's chicken welfare specialist Kate Hartcher questioned why Star Poultry Supply continued to operate while it was still under investigation.

She added: "We think that the abattoir should have been immediately shut down until all animal welfare risks can be avoided and any problems can be rectified."

"The abattoir shouldn't have been running at all."