An Israeli man has been arrested on suspicion of hacking into Madonna's computer and selling her unreleased songs online.
The 39-year-old was detained as part of a joint investigation by Israeli authorities and the FBI.
Israeli media said the man taken into custody was a former contestant on a popular singing contest on Israeli television.
Madonna said she was grateful to anyone who helped in the arrest.
"Like any citizen, I have the right to privacy," she said.
"This invasion into my life - creatively, professionally and personally remains a deeply devastating and hurtful experience, as it must be for all artists who are victims of this type of crime."
In December, unfinished tracks were leaked before the release of the singer's Rebel Heart album.
Israeli private investigator Asher Wizman said Madonna's team contacted his company several weeks ago to look into the matter after rumours of an Israeli connection to the leak.
Madonna, a devotee of Kabbalah, or Jewish mysticism, has visited Israel several times and chose Tel Aviv to kick off her 2012 world tour.
Mr Wizman said: "Our investigator found her computers, at home and at a studio, were broken into from a computer in Israel.
"We tracked down the computer, and the man behind it.
"After gathering enough evidence, we turned to the police and he was arrested."
Police say the arrested man is suspected of computer hacking, copyright violation and fraudulent receipt of goods.
The FBI said: "This case highlights the international scope of online criminal activity and the need for close co-operation between nations as we collectively identify and bring to justice those who pose a threat in cyberspace."