Israeli Prime Minister Benjamin Netanyahu has been charged with bribery, breach of trust and fraud, says the country's attorney general Avichai Mandelblit.
Mandelblit announced the indictment on Thursday, following several recommendations from Israeli police to take action.
In a statement, he said he had made a "heavy-hearted" decision and insisted it was not politically motivated.
"A day in which the attorney general decides to serve an indictment against a seated prime minister for serious crimes of corrupt governance is a heavy and sad day, for the Israeli public and for me personally," he said.
"This is not a matter of right or left. This is not a matter of politics.
"This is an obligation placed on us, the people of law enforcement and upon me personally as the one at its head."
Netanyahu has denied any wrongdoing in all the cases and is under no legal obligation to resign from his post.
He said on Thursday evening that the charges amounted to an "attempted coup" as part of "a false plot in the process of filthy and tragic investigations".
"They weren't after the truth," he said of the investigators during a televised speech, adding: "They were after me."
"An independent external committee should be set up to investigate the method and put an end to it.
"It's time to investigate the researchers. It is time to investigate the prosecutor's office confirming tainted investigations."
Netanyahu then went on to confirm that he had no intention of resigning from his position during the indictment process.
The three long-running investigations accuse Israel's longest-serving premier of accepting hundreds of thousands of euros worth of gifts in exchange for favours, and for negotiating better coverage in the national media.
He is facing up to ten years in prison for the bribery charge and three years for fraud and breach of trust, should he be convicted.
In one of the cases, Netanyahu is said to have accepted gifts totalling $264,000 (€238,000) in exchange for changes to tax exemption legislation.
Such gifts include cigars and champagne from a Hollywood producer and Australian billionaire, prosecutors have said.
The final two cases involve negotiations with the Israeli media to print more positive stories about Netanyahu and his family.
In the first, recorded conversations are said to prove the 70-year-old tried to negotiate less critical reporting on him in Yedioth Ahronoth, a national daily newspaper.
He is said to have offered in return to halt the publication of its competition, an outlet called Israel Today.
The second case accuses Netanyahu of years-long interference with the coverage published on the Walla website in order for it to lean more favourably toward him and his family.
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Thursday's indictment comes as the latest blow to Netanyahu and his Likud party amid an already unsettled political landscape in Israel.
The right-wing leader and his main opposition have both been unable to form a government following two elections this year.
Should this stalemate continue, a third election will be called in the next few weeks and could unsettle the 70-year-old's reign that he has held since 2009.