Police have called in a geographic profiler to help in the hunt for missing music teacher Jane Longhurst.
The expert, from the National Crime Faculty, will study photographs of the area where Miss Longhurst lives and pinpoint areas police should search.
Detectives are also liaising with forces around the country to check for possible links with other mysterious disappearances.
Miss Longhurst, 31, a teacher at Uplands School for children with learning difficulties, vanished from her home in Shaftesbury Road, Brighton, ten days ago, on March 14.
Police continued house-to-house inquiries in the area of her home today.
Meanwhile, heartbroken friends insisted the show must go on as they desperately clung to fading hopes she might still be alive.
The Musicians of All Saints dedicated their performance on Saturday to their viola player.
The seats where Miss Longhurst and her distraught partner Malcolm Sentance, also a viola player, should have been sitting were left empty.
The atmosphere throughout the performance was sombre as the hushed audience prayed for Miss Longhurst's safe return.
Hours before the concert at the All Saints Centre in Lewes, rehearsals were interrupted by detectives who interviewed all members of the orchestra.
Friends and family said she had shown no signs of depression and it was completely out of character for her to go off without telling anyone.
Police believe she may have been abducted and have extended their hunt nationwide.
Orchestra director and conductor Andrew Sherwood said Miss Longhurst's colleagues were "shattered" about her disappearance and found it "horribly hard" to perform.
However, they eventually decided she would have wanted them to go ahead.
Mr Sherwood told the full house: "This evening is quite difficult for everybody, the orchestra particularly. She was a lovely person - she is a lovely person. We ask you to keep her in your thoughts.
"Malcolm, her partner, would have been playing here as well. We have not replaced them. They are still with us.
"We thought that for Jane's sake and Malcolm's we would continue to play this concert.
"It is tough. We do not make any bones about it. We ask you to really remember her and we hope there will be a good outcome.
"It is a tribute to these players they have decided to continue. They have decided for Jane."
Mr Sherwood took Miss Longhurst's place for one of the pieces she was due to perform.
After the concert, he said: "It would have been better if she had done it - she is a better viola player."
Miss Longhurst's black leather Next purse is missing but there have been no reports of her credit cards being used.
Also missing is her blue-grey Nokia mobile phone and her keys, as well as some clothing.
Anyone with any information should call officers at Brighton police station on 0845 6070999.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article