Megan Stammers, who went missing a week ago with her maths teacher Jeremy Forrest has been found in France.
The 15-year-old has been taken into protection and Forrest, 30, has been arrested, Sussex Police said.
They were found at around 12.15pm today UK time, although police would not reveal the exact location. According to French media the pair were found in Bordeaux.
Megan Stammers has been found safe and well in France
The pair were both "safe and well", the force said.
Father Martin Stammers told Sky News: "We are just so so happy, we're over the moon. Whatever happens next, happens next but I just know she is safe and well and that she'll be back with us soon. It's such joy."
He refused to comment on Forrest, but paid tribute to Sussex Police for their work, and all the people who had spread the search for the teen on social networking sites.
Martin Stammers gives reporters a 'thumbs up' after the news broke
Forrest has been arrested on suspicion of child abduction.
They were found as a result of information that came after the case received media coverage in France, police said.
A statement issued by Sussex Police said: "Their families have been informed and arrangements will now be made for Megan and Jeremy's safe return."
Megan's natural father Barry Wratten told The Telegraph the news was "what he had been hoping and praying for".
Martin Stammers, Megan's stepfather, posted this picture on his Twitter account
"The past week has been absolutely terrible. You don't want to say it, but sometimes you think the worst.
"So this is wonderful news. It's brilliant. I can't say how relieved I am. I just want her back in the UK now with her family.
"My message to Megan would be that I love her very much, and that I am so glad she is safe. I'd also like to say that I am not angry with her at all - we all do silly things when we are young without thinking about the consequences.
"It might not seem like it to Megan right now, but this is the right thing and is for the best.
"But the main thing is that she is coming home. I am so, so pleased."
British police are said to be on their way to Bordeaux, who said the location of the pair was "a direct result of media coverage in France."
It comes after a British pensioner claimed she spotted Stammers in Paris.
Brigitte Ripley, 73, believes she saw the 15-year-old and her teacher Jeremy Forrest on the Champs Elysee.
Jim and Julie Forrest appealed for their son Jeremy to come home during a press conference
She told The Sun: "I noticed her as she had a similar bird patterned blouse to one of mine - I'm as sure as I can be that it was Megan.
"She was in front of me, a youngish girl with long, dark hair. She seemed well, she seemed fine. They were just like anyone else walking around in Paris. They looked like tourists."
Police appeals to find the pair were translated into French but there was confusion as to how intense the search was outside the UK.
It was reported that their details were not posted on Interpol's website under sections used to find missing people, and that French police were not carrying out a dedicated search for them.
However Jean-Philippe Joubert, state prosecutor for Boulogne-sur-Mer, told The Daily Telegraph: "If the couple are recognised and identified, then they will be arrested."
On Thursday Forrest's parents tearfully begged their son to "come home" during a press conference.
Jim and Julie Forrest appeared alongside Sussex Police's Chief Inspector Jason Tingley, urging him to "please, please, get in touch".
CCTV images from the Dover-to-Calais ferry revealed the pair holding hands
Jeremy Forrest, performing under the name "Jeremy Ayre"
In a quavering voice, Mr Forrest said: "Hi Megan, hi Jeremy, I hope this message reaches you and you are both okay.
"There are a lot of people back home that are desperate to hear from you.
"All I am asking is for one of you to make a call, send an email, so we know you are both safe.
"We are all here for you both. Please, please get in contact."
The last confirmed sighting of Stammers and Forrest - who taught maths at Bishop Bell C of E School in Eastbourne, East Sussex - was from CCTV cameras on board a Dover-to-Calais ferry at 9.30pm last Thursday.
The release of two images of the pair, arm in arm and holding hands, was intended to trigger a response from the public about their whereabouts.
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