Amazon has updated its Alexa voice assistant after it "challenged" a 10-year-old girl to touch a coin to the prongs of a half-inserted plug.

The suggestion came after the girl asked Alexa for a "challenge to do".

"Plug in a phone charger about halfway into a wall outlet, then touch a penny to the exposed prongs," the smart speaker said.

Amazon said it fixed the error as soon as the company became aware of it.

The girl's mother, Kristin Livdahl, described the incident on Twitter.

She said "We were doing some physical challenges, like laying down and rolling over holding a shoe on your foot, from a [physical education] teacher on YouTube earlier. Bad weather outside. She just wanted another one."

That's when the Echo speaker suggested partaking in the challenge that it had "found on the web".

The dangerous activity, known as "the penny challenge", began circulating on TikTok and other social media websites about a year ago.

Metals conduct electricity and inserting them into live electrical sockets can cause electric shocks, fires and other damage.

"I know you can lose fingers, hands, arms," Michael Clusker, station manager at Carlisle East fire station, told The Press newspaper in Yorkshire in 2020.

"The outcome from this is that someone will get seriously hurt."

Fire officials in the US have also spoken out against the so-called challenge.

Ms Livdahl tweeted that she intervened, yelling, "No, Alexa, no!"

However, she said her daughter was "too smart to do something like that".

Amazon told the BBC in a statement that it had updated Alexa to prevent the assistant recommending such activity in the future.

"Customer trust is at the centre of everything we do and Alexa is designed to provide accurate, relevant, and helpful information to customers," said Amazon in a statement.

"As soon as we became aware of this error, we took swift action to fix it."