west highland terrier puppy
A video showing dogs being injected with a substance thought to be acid has sparked outrage in Iran Wei-Hang Chua/Flickr

A video showing stray dogs being injected with a substance presumed to be acid in Iran has sparked outrage, prompting activists and celebrities to protest against animal cruelty.

The footage showed the dogs dying in agony after being injected in Shiraz, capital of Fars province. It was filmed by animal activists who alleged that the people who killed the dogs were paid $4 (£2.70) for each animal they injected with acid.

After the video circulated on social media, protesters gathered outside Shiraz's provincial department of environmental protection, demanding punishment for the killers, news agency IRNA reported.

Iran's Vice President Masoumeh Ebtekar called for an investigation and criticised the killings.

There should be "an immediate end to unconventional population control methods for stray dogs," she said in a letter published by another Iranian news agency, ISNA.

Ali Karimi, a retired football star who played for Bayern Munich, posted on Instagram a picture of his two dogs along with the message: "Dogs are the kindest domestic animals. I hope those who, under any excuse, did this to these animals get what they deserve."

This is not the first time that the Islamic republic has sparked controversy regarding the treatment of dogs and their owners. Last November, the country proposed a bill punishing dog owners with 74 lashes if they were caught keeping a dog at home or walking the animal in public.

The new bill, if passed, would also punish those charged with dog-related offences to pay fines up to 100 million rials (£2,363).

"Anyone who walks or plays with animals such as dogs or monkeys in public places will damage Islamic culture, as well as the hygiene and peace of others, especially women and children," the draft law stated.