Mariah Carey is being slammed by for accepting a $1 million in exchange for performing for Angola's president, whom the Human Rights Foundation calls a "notoriously corrupt" tyrant.

On Sunday, the superstar performed a two-hour concert at an event for the Angolan Red Cross and President José Eduardo dos Santos, who has ordered the deaths of a number of politicians, journalists and activists who have protested his rule, according to the Human Rights Foundation. Dos Santos first became president in 1979.

Carey also took a photo at the event with the president and his family, reportedly saying, "I am happy to be here in this room, and I am honored to share this show with the president of Angola," reports ABC News.

In response, HRF president Thor Halvorssen blasted Carey in a statement, saying "Mariah Carey can't seem to get enough dictator cash, reportedly more than $1 million this time," Halvorssen said, according to the Hollywood Reporter. "Just five years ago she performed for the family of Libyan dictator Muammar Gaddafi. Now, she goes from private performances to public displays of support and credibility for one of Africa's chief human rights violators and most corrupt tyrants. It is the sad spectacle of an international artist purchased by a ruthless police state to entertain and whitewash the father-daughter kleptocracy that has amassed billions in ill-gotten wealth while the majority of Angola lives on less than $2 a day."

A number of other celebrities have also been criticized for getting paid to appear at events involving a controversial ruler, including Jennifer Lopez, Kanye West and Hilary Swank.