After the announcement, the McCanns said being named suspects in the case had damaged the search for Madeleine.
"In an order issued today, ... the investigation into the disappearance of the minor Madeleine McCann has been halted because no evidence was discovered of any crime committed by the suspects," the attorney general's statement said. It added the investigation could be reopened "if new evidence emerges from any serious, pertinent and authoritative" source.
The disappearance of the blond-haired girl in May 2007 immediately attracted intense global media attention which continued unabated as her parents were named as suspects and few clues turned up to explain how she mysteriously vanished from a hotel room during a family vacation in Portugal's southern Algarve region.
She went missing a few days before her fourth birthday and there has been no reliable indication of what might have happened to her despite numerous reported sightings from around the world.
The McCanns have waged a far-reaching international campaign to find their daughter. Through regular statements to the media and via a Web page, they kept the search for Madeleine in the public eye.
Pope Benedict XVI blessed the McCanns, who are Catholics, and a photo of their daughter during his weekly general audience at the Vatican a few weeks after her disappearance. Celebrities, including "Harry Potter" author J.K. Rowling and soccer star David Beckham, made public appeals that helped raise money for a Find Madeleine fund.
The McCanns also traveled to Brussels, Morocco and Spain in their effort to raise public awareness of their daughter's disappearance. And they campaigned for the introduction of a Europe-wide child abduction alert similar to the Amber Alert system in the United States.
The ruling ends months of anguish for the three suspects who denied their involvement from the start and eases pressure on Portuguese police whose failure to make progress under intense public scrutiny at home and abroad.
The McCanns' reacted to the Portuguese decision by expressing their anguish over being named suspects.
"It is hard to describe how utterly despairing it was to be named arguidos (suspects) and subsequently portrayed in the media as suspects in our own daughter's abduction," Kate McCann told reporters in England. "Equally, it has been devastating to witness the detrimental effect this status has had on the search for Madeleine."
Rogerio Alves, one of the McCanns' Portuguese lawyers, children go missing worldwide each year and are never found.
