NEW DELHI — In early July, unidentified men threw acid on a 35-year-old woman while she was staying at a government-run women’s hostel in Lucknow, 330 miles southeast of here.

Guards came to her rescue, but the attackers fled. The assault on the woman, a gang-rape victim whose first name is Vimla, is the latest in a series of acid attacks that included two men forcing her to drink acid in March. USA TODAY does not use the full names of sexual assault victims to protect their privacy.

India has made international headlines for horrific rape cases in recent years, but acid attacks are common, too, although they receive less attention.

There are 250 to 300 acid attacks reported in India every year, despite laws restricting the sale of acid or other deadly chemicals, according to Stop Acid Attacks, a non-profit group.

Vimla “is a mysterious but tragic case of a woman being attacked repeatedly with acid,” said Asish Shukla of Stop Acid Attacks, which also runs a chain of cafes called “Sheroes Hangout Cafe,” managed by acid attack survivors like Vimla. 

Shukla said the group has demanded that India’s Central Bureau of Investigation to examine her case. “We are worried why she is attacked again and again over a long period,” Shukla said.

Dibyaloke Rai Chaudhuri, a coordinator at Acid Survivor Foundation India, said Vimla’s attackers targeted her repeatedly so she would be frightened into withdrawing the charges against them. So far, she has not. 

In 2016, India recorded 300 attacks but many go unreported, so the actual number could exceed 1,000, according to Acid Survivors’ Trust International based in the United Kingdom.