In the latest incident, an 18-year-old identified only as Najibullah was arrested on October 13 in connection with the gruesome torture and beheading two days earlier of a woman in the western city of Herat, near the border with Iran.
Mahgul, a 25-year-old newlywed, was found dead outside her home by her family, who then carried her mutilated body to the local Department for Women's Affairs to raise awareness of her killing.
Najibullah, who gave a confession in front of journalists and television cameras on October 15, said he was forced to carry out the act by his aunt, Mahgul's mother-in-law, Parigul. He said Parigul restrained Mahgul, while he took a sharp knife and beheaded her.
"My uncle's wife told me I should kill this person. I said I couldn't kill her. She told me, 'If you can't kill her, then help me do it.' She forced me and I helped her," Najibullah recalled.
"She took me inside her home and hid me. When [Mahgul's] husband left to go to the bakery, she told me to come out. She held her [Mahgul's] legs while I beheaded her," he continued. "I asked her [Parigul] why she wanted to behead Mahgul. She said, 'I hate her because she doesn't listen to me.'"
Herat's police chief, General Sayed Abdul Ghafar, said police had initially arrested Mahgul's mother-in-law, father-in-law, and husband, but later also arrested Najibullah after witnesses came forward to say they had seen him carrying a bloody knife as he left the crime scene on the night of the killing.
Ghafar, who said the four had yet to be formally charged, said the investigation concluded that the main motive for the crime was Mahgul's refusal to become a prostitute, a demand he said was made by her in-laws.
Mahgul's family, who expressed their shock at the brutal killing, rallied along with dozens of women's right activists outside a police station in Herat on October 15 to protest what they said were delays by the police in bringing charges over the crime.
In a statement released on October 17, Amnesty International strongly condemned the beheading. "The tragic fate of Mahgul is one more incident that highlights the violent atmosphere that women and girls face in Afghanistan and the region," said Suzanne Nossel, Amnesty International USA executive director.
Mahgul's murder comes after the body of a 30-year-old woman was found in Herat's Pamanare district at the beginning of October. The victim, who had had her nose, ears, and fingers removed, was taken to Herat regional hospital, where doctors said she was tortured before being killed.
Herat's district attorney office, who confirmed the authorities had yet to make any arrests in that case, said investigations were ongoing.
The two recent cases bring to around 20 the number of women slain this year, according to Herat's Department for Women's Affairs office, which added that family members were accused of involvement in most of the cases.
The slayings have worked to highlight the bleak situation for women in Afghanistan, where domestic abuse is routine, arranged marriages are the norm, and female suicide rates are among the highest in the world.
Afghan women have won back basic rights in education, voting, and employment since the Taliban were ousted from power in 2001, but many are still routinely subjected to domestic violence and abuse.
Herat, in particular, has been grappling with high levels of violence against women, mostly because it is one of the largest and most populous provinces in Afghanistan. The director of the local Department of Women's Affairs in Herat, Jamshidi Mahbubeh, says her office has documented more than 700 cases involving violence against women in the past year.
The cases, she says, include those involving domestic violence and abuse, torture, murder, physical mutilation, and women who have committed suicide.
Herat has the highest number of cases of self-immolation -- women who set fire to themselves -- in the country. Many try to commit suicide because they are subjected to domestic violence and abuse. Most cases involve young women burning themselves with household fuel or cooking oil. Nearly all suffer horrific scarring and in some cases the injuries result in death.
According to estimates by the Department of Women's Affairs, at least 80 women in Herat have died in the last year due to self-immolation.
Armand Halimzada, a human rights activist, says doctors, researchers, and activists have not come to any clear conclusions as to why there are so many self-immolation cases in Herat. There is, however, one prominent theory: "that this practice has roots in Iran and Afghan refugees returning from Iran have imported this culture."
Lailama Rahimi, a women's rights activist, has called on the authorities to do more to enforce a 2009 law on eliminating violence against women, which rights activists say is still only periodically enforced.
Rahimi says many women who have suffered from violence almost never receive justice. Even if their cases go to trial, she says, the majority result in the acquittal of the perpetrators, the dropping of charges to less serious crimes, convictions with shorter sentences, and female victims themselves being accused of "moral crimes" for making private matters public.
That failure, she says, is ensuring the culture of violence against Afghan women continues. "All the concerns we have today, we have had for a long time. The difficulties we [women] face are due to [Afghanistan's] tribal culture," she says. "This [failure by the authorities] is why we are seeing this violence against women continue."