The United States on Wednesday imposed targeted sanctions on two South Sudanese government officials and one former official, saying they had played roles in threatening the peace, security, or stability of South Sudan, and three companies that are owned or controlled by one of those individuals.

The Treasury Department sanctioned Gen. Malek Reuben Riak Rengu, the army’s deputy chief of staff in charge of military procurement, and Michael Makuei Lueth, South Sudan’s information minister. Sanctions were also imposed on Paul Malong Awan, the former army chief. Three companies owned or controlled by Reuben also were sanctioned.

The Treasury also released a Financial Crimes Enforcement Network Advisory alerting U.S. financial institutions to the possibility that certain South Sudanese senior political figures may try to use the U.S. financial system to move or hide proceeds of public corruption.

The United States said it stands ready to impose other measures against those responsible for undermining the peace, security, or stability of South Sudan.

“These actions send a clear message to those enriching themselves at the expense of the South Sudanese people that we will not let them exploit the U.S. financial system to move and hide the proceeds of their corruption,” said Sigal Mandelker, undersecretary for terrorism and financial intelligence.

“Treasury will forcefully respond to the atrocities ongoing in South Sudan by targeting those who abuse human rights, seek to derail the peace process and obstruct reconciliation in South Sudan.”

State Department spokeswoman Heather Nauert said in a statement that the administration will apply increasing scrutiny on South Sudanese officials. “This is a man-made crisis, and one the Government of South Sudan can stop,” she said.

Six million people in South Sudan face life-threatening hunger while more than four million people have been displaced from their homes, including two million refugees.