LAGOS, Nigeria (AP) — Widespread protests against Nigeria's police have turned violent as demonstrators have been attacked by armed gangs in the streets of several cities, according to witnesses.

Since the protests began more than a week ago, at least 10 people have been killed and hundreds injured, according to Amnesty International, which accuses the police of using excessive force against the demonstrators.

The violence has erupted as support for the protests has come in from Nigeria’s politicians and from the Black Lives Matter movement in the U.S.

Eyewitnesses said that a group of men armed with guns and machetes violently dispersed the protest early Thursday in the Ikeja neighborhood of Lagos, Nigeria's largest city.

“They were shooting and attacking people with machetes, I saw them injure someone,” Tola Afolabi, who was at the protest, told The Associated Press.

Other protesters in Lagos were attacked on Wednesday by a group of young men “who came with stones, clubs, and broken bottles,” said Nifemi Olatunde. A similar attack also happened in the capital, Abuja, on Wednesday, said witnesses.

Many demonstrators suspect the attackers were hired by police to break up the protests as the strength of the demonstrations grows across the country.

’Only an irresponsible government will hire thugs to engage peaceful protesters,” spokesman of the opposition People’s Democratic Party, Kola Ologbondiyan, said in a statement.

Youthful demonstrators leading the nationwide protests are demanding an end to alleged police brutality, which they charge includes extrajudicial killings and extortion. The protests have rocked Nigeria, Africa’s most populous nation with more than 196 million people, affecting the largest city, Lagos, the capital, Abuja, and other cities including Port Harcourt, Calabar, Asaba, and Uyo.

The demonstrations started last week, after a video circulated online which showed a young man being beaten, apparently by police in the Special Anti-Robbery Squad, or SARS, that is accused by human rights groups of widespread abuses.

“Detainees in SARS custody have been subjected to a variety of methods of torture including hanging, mock execution, beating, punching and kicking, burning with cigarettes, waterboarding, near-asphyxiation with plastic bags, forcing detainees to assume stressful bodily positions,” Amnesty International said in a report in June.

The protests are a product of the years of police brutality inflicted not only by the SARS unit but by other parts of the police force, including the anti-kidnapping unit, Okechukwu Nwanguma of the Rule of Law and Accountability Advocacy Center, a group advocating police reform, told The Associated Press.

In response to the #EndSARS protests, the Nigerian government announced it would disband the unit.

But the closure of the police squad has not satisfied the protesters who say they want to see an end to all police brutality, an end to corruption, and respect for human rights. Their demands include the release of all arrested protesters, justice for victims of police brutality and compensation for the victims and their families, as well as prosecution of those suspected to be responsible.

The demonstrators are encouraged by enthusiastic backing they've received in Nigeria and from the United States, said protester Timi Olatunju. International attention to the problem of police brutality has “contributed to the protests which have received support globally, including from the U.S. where international rapper Kanye West and Black Lives Matter have shown interest," said Olatunju.

Activists in the U.S. have sent support on Twitter.

“Much love to the courageous Nigerian #EndSARS activists. The movement for justice and dignity is global and I’m proud to see our kin rise up. There needs to be immediate end to the police brutality and extrajudicial killing of people in #Nigeria. #BlackLivesMatter #EndSarsNow,” tweeted Opal Temeti, of Black Lives Matter.

“#BlackLivesMatter rises with the Nigerian people and protestors! #EndSars,” tweeted the BLM account.

The protests began peacefully last week but police and their supporters are accused of violently attacking the demonstrators.

“These protesters have been met with violence and excessive use of force. ... Nigerians are skeptical of authorities’ pledge to end police atrocities because the past claims of reforming SARS have turned out to be empty words,” Osai Ojigho, director of Amnesty International Nigeria, said in a statement issued Thursday.

“That police are still using excessive force on peaceful protesters, leading to injuries and deaths in Lagos, Ughelli, Abuja and Ogbomosho, throws through the window claims of any commitment to ending violations of human rights by Nigeria police," said Ojigho.

On the government's side, Festus Keyamo, Nigeria's labor minister, said the man shown being beaten in the video that sparked the demonstrations did not die as was initially reported and has been discharged from hospital.

Keyamo said the continuing protests have disrupted daily life.

“People cannot go to work," he said. "People cannot earn their daily bread.”

In one area of Lagos, demonstrators held up placards saying “We Have No Leaders,” a criticism of President Muhammadu Buhari's government.