A family in Australia was shocked to find a live snake inside a bag of cos lettuce they bought from an Aldi supermarket.

Lesley Kuhn shared images of the snake inside the bag on the Facebook group The Mosman Living on Tuesday, and warned shoppers to be careful.

"Check packaged lettuces carefully. Last night my son found a baby pale-headed snake in with his baby cos lettuce from Aldi," Kuhn wrote. The images show the snake wrapped around lettuce leaves inside a bag.

Facebook users were baffled, with one calling it a "bizarre" incident, while others asked for more details.

"Was it still alive?" one asked, while another wrote: "That is bizarre. What did he do next?" Many Facebook users called the find "awful" and "nasty."

One Facebook user joked: "Lucky. I never get a free pet snake in my shopping."

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The woman responded to the questions, revealing the snake was "very much alive." She added her son was okay, though he "hadn't realized how dangerous it was."

Kuhn said she contacted WIRES, Australia's largest wildlife rescue organization, who arrived to do the "highly unusual" rescue.

“We’ve never seen anything like this,” John Grant from WIRES told ABC News. “We assume, and it’s only an assumption, that because it was a juvenile it was picked with the lettuce and it’s survived the whole process.”

The reptile was later identified as a pale-headed snake, a "potentially dangerous species," according to Queensland Museum. The venom of these snakes is haemotoxic, and can cause "serious" damage. These snakes are generally found living in the hollowed trees with rough barks in New South Wales and Queensland.

An Aldi spokesperson told Yahoo News Australia they were investigating how the snake got inside the bag.

"We’ve worked with the customer and the team at WIRES to identify the snake’s natural habitat, which is certainly not an ALDI store! We thank WIRES for their support on this," the spokesperson said. "We are working closely with our produce supplier to investigate how this incident could have possibly occurred."

Representational image pixabay