The pair were 'strolling hand-in-hand' in the centre of Bordeaux's main shopping area when they were apprehended, said a local police spokesman.
Officers received information from a number of sources, both British and French, and were acting on a 'specific tip off' before Forrest's actual arrest, said the officer.
He added: 'The schoolgirl was safe and well, while the man with her was also in good health.'
Forrest was made 'garde a vu' - a French legal expression which effectively means a suspect is in custody and facing charges.
He is expected to be held for a number of days while diplomatic formalities are dealt with, including likely requests for extradition back to the UK.
British police are said to be on their way to Bordeaux, which is some 365 miles from Paris, or around seven hours drive.'
A Sussex Police spokesman said the huge media appeal had helped trace the duo.
They said: 'The information which led to them being located came as a direct result of media coverage in France.
Read more:
Megan Stammers: Schoolgirl and maths teacher Jeremy Forrest found in France | Mail Online
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