A few months ago, amid much fanfare, Facebook started rolling out its new tool against fake news which warns users when they try to post fake stories on the platform.

The feature, announced in December is the result of a collaboration with "third-party fact-checking organisations" -- such as Snopes and The Associated Press in the US and Full Fact in the UK.

However, that doesn't seem to have stopped blatantly fake stories from growing on the social network.

The most recent example is a story alleging that a baby "miraculously" survived twelve days after the Grenfell Tower fire in London

The story "quotes" detective superintendent Fiona McCormack as saying the baby was on the 16th floor and mentions tweets from the police and the Mayor of London Sadiq Khan.

However, no quotes from McCormack were released to the media regarding that particular episode. A quick look at Met Police and Khan's twitter feed show no mention of a baby being rescued.

The site in question, metro-uk.com, has posted several other hoaxes in the past, and its Facebook page is connected to other infamous hoax websites.

This time, it has been fooling people with a particularly nasty trick.

It uses the BBC's "breaking news" holding image so that when a story is posted on Facebook it seems legit:

A URL like that should immediately raise your suspicion level, but it hasn't stopped many people from sharing it on Facebook. Since Sunday, when it was published, the hoax was shared a total of almost 350,000 times:

The Facebook users above subsequently deleted the story, which has been shared on Twitter as a "miracle":

Tweet may have been deleted

Tweet may have been deleted

Tweet may have been deleted

Others flagging it as a hoax:

Tweet may have been deleted

Mashablebegan the process of sharing the story on Facebook to see if it triggered a red alert in the pop-up window.

No warning could be seen:

Mashablereached out to Facebook to seek clarity on the number of complaints needed for a story to trigger a suspect fake news warning, or for it to be taken down. We will update this post accordingly.

At the time of publication the fake story was still on Facebook.