Meir Dagan, a former Israeli general and longtime director of the country's spy agency, died on Thursday. He was 71.

Dagan directed the Mossad from 2002 until he retired in early 2011. Under his leadership, the Mossad reportedly carried out covert attacks against Iranian nuclear scientists and unleashed cyberattacks, including the Stuxnet virus, developed in cooperation with the United States. That digital weapon reportedly delayed the Iranian nuclear program.

Israel has never publicly confirmed any role in the Stuxnet attacks, but its involvement is widely assumed both inside and outside the country.

Born in 1945 in Ukraine to Holocaust survivors, Dagan reached the rank of general in the Israeli army and was known for innovations in battling terrorism. In the 1970s, he pioneered what became the "Mistaravim" unit, in which Israeli commandoes go undercover as Palestinians to capture militant suspects.

Dagan was appointed to head the Mossad by the late former Prime Minister Ariel Sharon, and shared his tendency to disregard traditional protocol to achieve military goals, said Ronen Bergman, who covers intelligence affairs for the Israeli daily Yedioth Ahronoth and is working on a history of the Mossad.

Dagan's operations against the Iranian nuclear program restored pride in the Mossad after botched overseas operations, Bergman said. Dagan also cultivated ties with intelligence agencies in other Middle Eastern countries who shared Israel's fear of Iranian nuclear aspirations, he said.

Nevertheless, Dagan's career also had some embarrassments. Under his leadership, the Mossad was believed to have assassinated Hamas operative Mahmoud al-Mabhouh in a brazen operation in his Dubai hotel room in 2010. Hotel CCTV footage captured apparent assassins disguised as tennis players. A number of countries accused the Mossad of forging passports under their citizens' names for the suspected killers to use. Israel has never confirmed or denied involvement.

In recent years Dagan became a fierce opponent of a military strike on Iran. He openly criticized Prime Minister Benjamin Netanyahu's opposition to the recently implemented nuclear deal between Iran and world powers.

Days before Israel's elections last March, Dagan headlined a Tel Aviv rally and tearfully implored voters to vote out Netanyahu.

"He was concerned that we, the generation that achieved statehood, are leaving our children and grandchildren a state that is not better than the one we had," former Mossad chief Danny Yatom told Israel Radio.

Despite their differences, Netanyahu helped Dagan arrange a liver transplant in Belarus in 2012 after he could not undergo the procedure in Israel due to his age.

Israel Radio reported Thursday that Dagan's corneas would be donated.

Netanyahu remembered Dagan as "a daring fighter and commander."

"A great soldier has passed away. May his memory be a blessing," Netanyahu said.

Dagan was known for carrying a photograph of his grandfather being humiliated by Nazi soldiers shortly before being murdered.

Israeli President Reuven Rivlin said Dagan "symbolized for many the rebirth of the State of Israel from the ashes of the Holocaust."

Dagan is survived by his wife and three children.