In 2007, then three-year old Madeleine McCann went missing in the Algarve region of Portugal.
The investigation continues a decade later. In April, Assistant Met Commissioner Mark Rowley confirmed detectives were still probing a 'critical lead'.
For Halloween 2017, one man decided to dress up as the missing child.
Daniel Gearie, 25, from Dundee, shared a photo of his costume on his Twitter account, which has since been made private.
Under the caption 'You've taken it too far Daniel', Gearie shared a photo of Madeleine McCann wearing an Everton shirt, alongside a photo of himself in the same shirt, and a blonde wig.
According to The Sun Gearie also posted:
And before you say 'this is sick' etc I know it is but I'm not the one who left a child unattended in a Portuguese hotel.
A spokesperson for Madeleine's parents Kate and Gerry McCann told The Sun:
Kate and Gerry think he's an idiot and at his age should know better. What he did was deeply offensive and cruel.
'Sick' Halloween costumes are not uncommon, but they usually mock the aggressor (such as costumes of Jimmy Saville), rather than the victim of a criminal and horrendous act.
Gearie, who received heavy criticism in comments on social media, regarding the costume, later said he 'regretted' the incident. The now hidden post, is quoted by The Sun as reading:
On reflection my costume for tonight is in very poor taste, I'd like to apologise to all those who have been offended.
I've already admitted earlier it's something I regret however I need to be open and honest about what I've done, can't hide from it.
Screen captures of an additional statement have also been shared online.
HT The Sun