KUALA LUMPUR:  Malaysian Prime Minister Najib Razak, stung by allegations that he received some $700 million in government money, on Tuesday fired the attorney general who had been investigating him and a deputy who has been among his most prominent critics.

Najib is under increasing pressure over leaked confidential documents that allegedly show that the money, from state investment fund 1MDB, went into his personal accounts.

Najib announced over national television Tuesday that his deputy Muhyiddin Yassin will be replaced by Ahmad Zahid Hamidi, the former home minister. He also dropped four other ministers to strengthen his administration and ensure they can "work as a team."

"The decision to replace Muhyiddin was a very difficult one, but I had to do it so a strong team can move forward," Najib said.

Muhyiddin has been critical of the government's handling of 1MDB's massive debt and has called on Najib to explain the alleged funds transfer.

Earlier Tuesday, the government announced it had terminated the services of Attorney General Abdul Gani Patail due to health reasons. Gani, when contacted by Malay Mail Online, said he had not been aware of the decision.

Gani confirmed earlier this month that he had received documents from investigators that linked Najib and 1MDB. The existence of the documents, which allegedly show $700 million was wired from entities linked to 1MDB into Najib's accounts, were first reported by The Wall Street Journal.

Najib has not disputed the existence of the accounts or the receipt of the funds. He has only said that he has never used government funds for personal gains, and called the allegations a political sabotage.

The documents sent to the attorney general pave the way for possible criminal charges, which would be a first for a Malaysian prime minister.

Najib's ruling National Front coalition has been in power since independence from Britain in 1957. However, support for the coalition has eroded in the last two general elections. In 2013, it won the polls but lost the popular vote for the first time.