An image of missing British girl Madeleine McCann was used to sell online vouchers for discounted vacations in Portugal, the country where she went missing more than five years ago.

The image was taken just hours before the then 3-year old McCann went missing from her family's holiday apartment in Praia da Luz.

VoucherDigg used McCann's image in an advertisement boasting '£20 off: Great discount on holiday bookings,' reported the Daily Mirror.

Clarence Mitchell, the McCann family spokesperson, told the Daily Star that the use of the image was appalling insensitive.

This is an appalling use of Madeleine's picture and whether it is a result of hacking or a mistake it must be removed immediately, said Mitchell according to the Daily Star.

That is the last picture of Madeleine that was taken on the holiday in 2007 just before she was taken, and for someone to use it -- as some sort of sick joke it would appear -- advertising holidays to Portugal of all places, is just appalling. There is no excuse for it, Mitchell said according to the Huffington Post.

Kate and Gerry are fully aware of this and are horrified. We understand it has been on the website for 24 hours, said Mitchell according to the Daily Star.

Underneath the image is a caption that says best value. After clicking on it users are taken to another page from lowcostholidays.com that offer similar vacation packages.

The Daily Star reported that the advertisement encourages people to hurry up for time is limited. Take the ones you loved and enjoy your life.

Carter-Ruck, a London law firm, has been asked to demand the removal of the image.

Lawrence Hunt, the boss of lowcosttavelgroup said he was outraged at the use of the photo. He said a Chinese marketing firm had decided to use the photo.

We have no contract with VoucherDigg to advertise our holidays and we are doing all that we can to contact the website and get the picture removed. We discovered this vile material yesterday and immediately broke all the [web] links to our site and contacted our lawyers, Hunt told the BBC.

VoucherDigg declined to comment.

McCann, a then 3-year-old child, went missing while on a family vacation in Portugal on May 3, 2007, just nine days shy of her fourth birthday. She disappeared from her family's apartment in Praia da Luz while her parents were dining at a nearby tapas restaurant with their friends.

In 2011, McCann's parents wrote to British Prime Minister David Cameron asking him to look into the case.

Cameron ordered a new probe by British police.

Around 37 investigators poured through 100,000 pages of evidence from British and Portuguese officers on the little girl's disappearance, leading them to identify 195 investigative opportunities.

According to the Sun, investigators say a child matching McCann's description was seen at a campsite three days after being reported missing. A German family was seen with the child. They arrived at a lodge and requested extra rooming to accommodate the child.

She [the girl] seemed alienated and completely different to her family. It really was most peculiar, said witness Karen Sisson. The police were notified but did nothing. The family stayed at the lodge for at least two weeks, reported the Sun.

Sisson said the girl seemed groggy and out of it. Investigators believe if it was McCann, then she could have possible been drugged. The German family could have been using fake license plates to avoid detection.

This lady has done exactly the right thing in reporting what she saw to police, said a spokesman for the McCann family according to the Sun.