Robots under investigation after alleged incident involving a child while making a delivery in Milton Keynes

But the company behind the robots, Starship Technologies, is taking the alleged incident seriously and has launched an investigation.

A parent reported on the Nextdoor app that her toddler son had received a knock from a robot while they were out shopping last week.

She wrote: “So today my two year old son was hit and pushed by one of those delivery robots in the Brunel shopping centre in Bletchley. The robot never stopped and continued his journey.

"My son didn’t get any injury but he was scared and stressed after this.”

The mum said she wanted to raise awareness that the robots may not always stop when they are close to people.

"I really hope this doesn’t happen again,” she added.

The mum complained to Starship and was offered a £5 discount, which she refused. "I told them that what I wanted was for them to check the situation and never repeat it again because there are vulnerable people out there.”

The post got a mixed response, with opinion divided between blaming the robot and defending it.

One poster said they had even conducted their own experiment. They wrote: “I stood in front of one a couple of years back to see what happened. It stopped and spoke and politely asked me to move. I stayed there for a second and it went round me.”

Another wrote: “I think the sensors get confused. One almost went into my husband a few weeks ago.”

One poster reported that her friend’s dog had been knocked by a robot. The dog allegedly “got a nudge but it was no big deal”, they said.

“She just acknowledged she should have been looking where her dog was.”

Other robot fans stuck up for the machines and would hear no criticism. “I come into contact with them on a regular basis and they always recognise me,” wrote one.

Another poster pointed out: “These are machines and surely you would see one coming as they have lights on them. If I were walking with a child I would treat them with uncertainty like I would a bike or dog. I don’t think it’s the robot’s fault.”

But some people could see both sides of the debate. “It’s good to report these incidents as robots are not perfect. As anything electronic it can fail. Starship should investigate these incidents,” wrote one person.

The Citizen asked Starship for a comment and a spokesman told us: “We take an incident like this seriously and we’re investigating.”

Starship robots launched in Milton Keynes in 2018 and have boomed in popularity ever since, delivering to more and more areas of the borough. They have a partnership with the Co-op and Starbucks, plus a host of other independent takeaway stores.

They are now an established part of the community, with many people greeting them as they trundle past.

The pioneering delivery bots can already speak to people, using a few simple phrases, but one of their latest achievements is learning to sing.