Monica Esperza Castro was driving with her husband and her brother on 12 February, 2013 when police from Torreon, Coahuila state, took them to a warehouse behind the offices of Municipal security department in Torreon. First, they reportedly beat her husband and brother after which the officers grabbed Monica and began to simulate drowning by plunging her head into a bucket repeatedly. They then suffocated her with plastic bags, beat her buttocks with a wooden board and dragged her along the floor by her hair.

The municipal police allegedly applied electric shocks to her legs and her genitals. A representative of Torreon security department raped her in front of her brother and her husband. Six officers, one after the other, raped her and forced her to perform oral sex, while uniformed army officers looked on.

The officers then took the three of them to the PGR (Attorney General) in Torreon. As a result of torture, Castro's husband died on the way to the Attorney general's office. She was later flown to the offices of the Deputy Attorney General on Organised Crime (SEIDO) in Mexico City where she was forced to sign a confession saying that she was part of the Zeta drug cartel.

In August 2014, forensic experts from the National Human Rights Commission confirmed that she had been raped. Castro is in prison awaiting the outcome of her trial on charges of involvement in organised crime.

Monica Castro is one of the number of women illegally arrested, tortured and abused by Mexican police looking to boost arrest figures to justify the war on drugs, Amnesty International said in a report released on 28 June.

The human rights organisation interviewed over 100 women who had reported sexual violence during the arrest along with sexual harassment and psychological abuse, including misogynist and sexualised insults and threats.

Electric shocks or beatings on certain parts of the body; suffocation with plastic bags to near asphyxiation; groping of breasts and pinching of nipples; rape with objects, fingers, firearms and the penis are some of the forms of violence inflicted on women to get them to confess serious crimes. The vast majority of the women arrested were young, poorly educated single mothers. Ten women were reportedly pregnant during the time of arrest while eight subsequently suffered a miscarriage.

Tailyn Wang, another woman who was two months pregnant at the time of arrest from Mexico City, was tortured and raped by the police until she miscarried.

Wang told the Guardian from prison: "Instead of investigating the torture I suffered, the whole system has ignored it, including the doctors, who instead pressure me to take psychiatric drugs to shut me up."

According to the report, of the 100 cases examined, most of the arrests were carried out by the federal police followed by state police, the army and the navy. Rape was reportedly used by police at all levels: municipal, federal, state, army and the navy.

In April 2016, a video was leaked to the press showing police and military officials suffocating a woman with a plastic bag and interrogating her while she screamed. An unprecedented apology was issued by the minister of defence and the National Security Commissioner.

Amnesty found that despite the introduction of various protocols and training programmes to tackle the problem, only a handful of perpetrators were held accountable and prosecuted. Research also showed that inadequate medical examination and poor documentation of detainees contribute to impunity and stop victims from getting justice.

Only two women, who had nothing to gain from participating in the research admitted they were guilty. Since former president Felipe Calderon first deployed tens of thousands of armed forces on the street to deal with drug cartels and organised crime, reports of torture have increased in Mexico.