Several dozen women in Kenya said police officers attacked them during this year’s election season and some said they were raped by men in uniform, Human Rights Watch (HRW) said on Thursday.

More than 70 people were killed in an election in August, later nullified by the Supreme Court, and a repeat presidential poll in October won by President Uhuru Kenyatta. The opposition boycotted the repeat poll and said it would not be fair.

The sexual attacks, mostly on women, occurred over this period in some of Nairobi’s slums and in two opposition strongholds, Kisumu and Bungoma, in western Kenya, HRW said in a report.

Kenyan police dispute rights groups’ allegations that officers used excessive force to quell election-related unrest. They did not respond to a request from Reuters for comment on the report.

One 28-year-old woman in the Nairobi slum of Mathare told Reuters: “Four men in police uniforms burst into my home and my children were sleeping, they pulled my husband out. One grabbed my neck, the other pulled off my clothes, another beat me with a stick, and the other forced sex on me.”

The woman who declined to be identified said she was four months pregnant and miscarried shortly after the rape. “I was bleeding and confused afterwards,” she said.

Another woman, aged 26, said: “Two men dragged me away from my friend, stripped off my clothes and one raped me as another one held me down.”

“Kenyan women who have been raped – they are lonely and abandoned and ashamed,” said HRW researcher Agnes Odhiambo. “It’s the Kenyan government who should feel shame for failing to protect them and help them get medical treatment.”

Kenyan rights groups accuse police of brutality and extrajudicial killings.

A government civilian watchdog tasked to oversee the police exists, but few officers are charged and convictions are extremely rare.

The sexual violence mirrored widespread violations against women after a disputed 2007 vote, when 1,200 people were killed, HRW said. At the time, the group documented at least 900 cases of sexual violence but said this was likely an underestimate.

“The new cases related to the August and October 2017 elections demonstrate a disturbing continuum,” Tina Alai, a lawyer with New York-based Physicians for Human Rights.

“Police have continued to perpetrate sexual violence against civilians they are obligated to protect,” she said.