Roderick McDonald, 76, was reportedly living in the Algarve when Madeleine McCann disappeared in 2007.
APRIL JONES GRAN ON MADDIE MCCANN: HER PARENTS WON'T WANT HER TO BE FOUND
He has been on the run for 22 years, after previously being seized in Thailand as part of an ongoing operation by the British Serious Organised Crime Agency.
The wanted man reportedly fled to Australia in 1988 while awaiting trial for repeatedly abusing an underage girl, only to be arrested again in Australia for sexually abusing another child the following year.
Released on bail, he then absconded to New Zealand, where he was again accused of abusing young girls. He managed to escape once again, but was caught by Interpol in Portugal in April 2010, while he was reportedly living on a campsite in the Algarve.
KATE AND GERRY MCCANN REVEAL OUTRAGE OVER CLAIMS THEY HID THEIR DAUGHTER'S BODY
Sources close to the Madeleine McCann investigation have indicated that McDonald has 'vital evidence about a suspected paedophile ring that operated across the Algarve region of Portugal in 2007', around the same time that the little girl was abducted.
The Mirror quotes a source as saying: “Roderick Robinson is a notorious and dangerous sex offender. He has shown a pattern of disturbing behaviour wherever he has travelled." **
**
McDonald was also given a suspended prison sentence in 2012 for abusing five and seven year old girls in Brighton who, according to reports, "bore a resemblance to Madeleine".****
Gerry and Kate McCann have reportedly said it was "unbelievable" police missed the chance to quiz him about Madeleine's disappearance.
Kate has been quoted as saying: "The police knew he was in Portugal around the time she vanished, but they let him slip through their fingers.
"They told me they would monitor him.
“When he fled they didn't even bother telling me. I am so angry he has been allowed to go on the run."
McDonald was apprehended yesterday in Gozo, and will be extradited to the UK to serve a prison sentence.