Police in Portugal have arrested the man accused of murdering Rikki Neave after he fled the UK.
James Watson was arrested in April on suspicion of murdering the six-year-old in 1994 but escaped from the UK in a mobile home after being released on police bail.
The 35-year-old was arrested in Lisbon around lunchtime on Tuesday and will remain in custody while extradition proceedings begin.
The schoolboy was found naked and strangled in a patch of woodland in Peterborough in 1994.
His mother was originally charged with his murder, but after a jury found her not guilty in 1996 the case has remained unsolved.
The arrest came days after it emerged Watson was posting pictures of himself on social media showing him drinking beer and enjoying the sunshine.
In a string of Facebook messages he said: "The best thing is I don't even have a passport. I just walked out of our country.
"Me and a mate left the UK in a mobile home.
"Booked it on the ferry, drove on and that was that. No checks, nothing."
He said he was creating some fun memories for the “dark days” to come and said the charges were “all b*******”.
His arrest followed a collaboration between the Major Crime Unit, national authorities and authorities in Portugal.
Watson has been arrested under a European Arrest Warrant on suspicion of breaching his licence.
Officers from the Bedfordshire, Cambridgeshire and Hertfordshire Major Crime Unit are expected to travel out to Portugal in the coming days.
Additional reporting by PA