The U.K. investigation into the disappearance of Madeline McCann, a young girl who vanished nearly a decade ago, has so far cost taxpayers $15.7 million, with an additional $3.1 million set aside for next year.

Minister Lord Bates revealed the figure in response to a written parliamentary question. The nearly $16 million price tag alludes to the cost up to June 2015, and the figure will likely rise before the end of the year, according to the Mirror.

McCann was almost four when she disappeared from her family's vacation apartment in the Portuguese resort town of Praia de Luz on May 3, 2007. The case and search for the missing girl has become one of the most famous of its kind of all time.

McCann's parents left her and her younger twin sisters asleep while they went out with friends to dinner at a local tapas restaurant. Upon their return, mom Kate raised the alarm after realizing her daughter was missing.

Since then, a series of suspects have been questioned, but there have been no solid clues, according to CNN. In the case's latest development last year, British police dug a wasteland close to where she went missing, but the search was deemed inconclusive.

The girl's parents, Kate and Gerry McCann, launched a massive campaign after she went missing, reported the Daily Mail. They believe she is still alive, and are "extremely grateful" for the allocation of money used in the investigation.