New security laws went into effect Monday in Malaysia.
Critics say the new measures give Prime Minister Najib Razak sweeping emergency powers which could be used to trample on human rights.
The new law enables Najib to suspend civil liberties whenever he believes there is a security threat.
Josef Benedict, Amnesty International's deputy director for South East Asia and the Pacific, said "the government now has spurned checks and assumed potentially abusive power."
The United Nations human rights regional office said it was "gravely concerned" that the laws may encourage human rights violations and lead to "unjust restrictions" on free speech and assembly.
The new legislation was passed as the prime minister is embroiled in a corruption scandal. Critics see the new laws as a way for Najib to hold on to power.
The prime minister has been under fire since revelations surfaced that he received about $700 million in his private bank accounts that appeared to have come from the state-owned investment fund 1Malaysia Development Berhad or 1MDB. Najib has denied all accusations of wrongdoing, insisting the money was a political donation from someone in the Middle East whom he has refused to identify.
In the largest initiative of its kind by the U.S. Justice Department's Kleptocracy Asset Recovery Initiative, authorities in the United Sates have initiated measures to seize more than $1 billion worth of luxury real estate, artworks, jewelry and even rights to a Hollywood movie that authorities allege were obtained with assets stolen from the 1MDB fund, which Najib founded in 2009 and now is owned by the finance ministry that the prime minister controls.
A spokesman for the prime minister has said the government will cooperate with any international probes. "As the prime minister has always maintained, if any wrongdoing is proven, the law will be enforced without exception."
The court filing alleges funds were laundered through bank accounts in the United States, as well as Luxembourg, Singapore and Switzerland.
The suits claims the stolen funds were used to buy penthouses, mansions, artworks and a private jet, as well as for hiring musicians and celebrities to attend parties.
Besides Malaysia and the United States other governments have been investigating 1MDB, including Singapore and Switzerland.