Authorities in Britain on Monday published two electronic images of a man they said was of "vital importance" in McCann's case. The images, along with photos of other persons of interest, were shown on the BBC program "Crimewatch."

McCann, then 3 years old, vanished from her family's apartment in the south coast resort of Praia da Luz in 2007. A Portuguese police inquiry into her disappearance was closed five years ago and she remains missing. In July, British police began a new investigation and on Monday they said the latest published images may depict her kidnapper.

"The sighting was during the evening of the 3rd of May around 10 p.m., and was of a man walking down the street with a child in his arms," Detective Chief Inspector Andy Redwood, the top investigator for the case, told the BBC .

"The child was described as about 3 to 4 years old, with blonde hair, possibly wearing pajamas. That's why we're so interested in this particular incident," he added. "This could be the man who took Madeleine."

Possibly planned

Redwood said her abduction appeared to be a planned crime and that police were also searching for a different man seen 45 minutes later who an Irish family said was holding a child matching McCann's description.

British police said they were offering a new reward of up to 20,000 pounds ($32,000, 23,000 euros) for information that could lead to her whereabouts.

McCann's parents, Gerry and Kate, told "Crimewatch" they still thought she would be found.

"We're feeling hopeful," said Gerry McCann. "These cases can get solved."

"It doesn't matter how much heartache we put ourselves through as long as we get the result that we need," Kate McCann said.

dr/hc (AFP, Reuters, dpa)