The mother of missing Swiss twins - whose father confessed to killing them before committing suicide - has joined a police search for her daughters.
Irina Lucidi boarded a French police helicopter to search for the six-year-old girls on the island of Corsica.
The father, Matthias Schepp, and the twins were last seen on a ferry from mainland France to Corsica on 31 January.
On 3 February, Mr Schepp threw himself under a train in Italy.
Irina Lucidi - and her brother - arrived on Corsica on Sunday and immediately joined the search with French and Swiss officers.
The police are focusing on the area between Propriano, south-west, and Bastia, north-east, from where Mr Schepp left Corsica - apparently alone - before committing suicide.
Mrs Lucidi said she had "not lost hope" of finding her children.
She reported Alessia and Livia missing on 30 January, after her estranged husband had failed to return the girls to their home in St Sulpice, Switzerland.
The 43-year-old had been looking after the twins for the weekend.
Earlier this week, the police revealed that Mr Schepp had written a letter saying that he had killed his daughters.
"The last envelope dated February 3 contained a letter in which the father said he killed the two girls, saying he was in Cerignola [southern Italy] where he was about to kill himself," police spokesman Jean-Christophe Sauterel said.
"I can confirm that in his letter he also said that they did not suffer and were resting in peace."
He picked up the girls on 28 January, before travelling to France and Italy. He was found dead in Cerignola, in the region of Puglia.
Swiss police have already revealed that Schepp had trawled websites on ferry schedules, suicide, guns and poison before taking the girls.
"We are dealing with someone who was extremely meticulous and who planned a certain number of things, including his trip to Corsica," Mr Sauterel said on Thursday.
Swiss media have carried a statement from Schepp's family saying he must have suffered a breakdown.