US rapper Nicki Minaj has gone ahead with a concert in Angola despite a rights group asking her to cancel it.

The Human Rights Foundation (HRF) said in a letter that the money to pay her came from "government corruption and human rights violations".

Minaj, 33, entertained thousands in the Angolan capital, Luanda, on Saturday.

The Christmas event was hosted by mobile phone company Unitel, which is part-owned by the family of Angola's President Jose Eduardo dos Santos.

Since the end of the conflict in 2002, Africa's second-largest oil producer has witnessed an economic boom, but critics of the elected government say the wealth has only benefited a small elite.

HRF's Thor Halvorssen wrote in the letter to Minaj last week that her participation in a performance sponsored by a government "involved in gross human rights violations would be improper".

Mr Halvorssen points out that Unitel is controlled by Isabel dos Santos, daughter of the president and said to be Africa's richest woman.

Transparency International recently named the billionaire as one of 15 symbols of grand corruption worldwide.

Two days after the accusation, Ms Dos Santos's company Fidequity issued a statement insisting it is an independent company and does not use public funds.

Before going on stage on Saturday, Minaj posted a photo of herself with Angola's flag on Instagram along with one of her posing with Isabel dos Santos with the words: "She's just the 8th richest woman in the world. (At least that's what I was told by someone b4 we took this photo) Lol. Yikes!!!!! GIRL POWER!!!!! This motivates me soooooooooo much!!!!"

Minaj also shared the stage with several local acts.

Her performance came a day after a judge ordered the release of 15 Angolan activists, including prominent rapper Luaty Beirao, who were arrested six months ago during a book reading where one of the books on the agenda was about non-violent resistance to repressive regimes.

The group will return to court next month for their trial's conclusion on charges of "rebellion" and attempting to carry out a "coup".

Minaj is not the only performer to be criticised by rights groups for their choice of gigs.

Singer Jennifer Lopez was criticised in 2013 for singing Happy Birthday to the leader of Turkmenistan, who was accused of human rights violations.

In 2011, Nelly Furtado said that she would give away $1m (£615,000) she was paid to perform for the family of Libyan leader Muammar Gaddafi.