Claudia Lawrence disappeared in March 2009 under the suspicion of the murder of missing chef Claudia Lawrence have arrested 59-year-old man from York.
Miss Lawrence, the 35 was, was gone when she is at home in the city in 2009, not found, North Yorkshire Police said.
A force spokesman said forensic examinations were carried out and expected to be several days.
Police said a car was seized and more arrests could not be ruled out.
The force did not say where the new forensic examinations take place.
Miss Lawrence, who lived in Heworth, had worked at the University of York and was due to start a shift at 06:00 on 19 March but don't show up.
She was reported missing from her father, Peter, 67, on the following day.
Extensive searches of the area were, but she was not found and police treated her disappearance as a murder there.
North Yorkshire Police launched a review of the case last year and have conducted new forensic work and searches of Miss Lawrence home.
Miss Lawrence was by her father Peter missing logged
new fingerprints were set free, while a fresh forensic examination of Miss Lawrence home
multiple complaints were in the BBC CrimeWatch since Miss Lawrence disappear
A DNA profile of a man was found from a cigarette end into Claudia Lawrence's car
A fresh appeal was made on the fifth anniversary of their disappear information in March was broadcast in the BBC CrimeWatch.
Police revealed several new lines of inquiry generated by the review of the case and a fresh examination of her homeland.
In 2009 discovered fingerprints with techniques, have been unavailable, they said.
A DNA profile of a man was on a cigarette end Miss discovered Lawrence's Vauxhall Corsa found.
North Yorkshire Police, said Lawrence family had been informed the arrest and were offered support.
Martin Dales, in favour of Peter Lawrence told BBC Radio York the family were "very encouraged" by the news of the arrest.
"It is the first time someone had been detained in that Claudia has been missing all five and a bit years", he said.
Mr Dales added: "Peter and the family want answers and they need some closure. If this results in this direction then this will be welcome."
