NEW DELHI, Sept. 25 -- A string of rape cases in India has reignited debate over women's safety and raised questions about why sweeping legal reforms and tougher punishments have failed to curb sexual violence.

Hundreds of students marched through the streets of New Delhi on Wednesday, shouting slogans and holding placards demanding stronger safety measures following the latest high-profile case.

In that incident on Monday, three men posing as police officers allegedly gang-raped a 17-year-old girl in a public park in the heart of the capital city, according to authorities.

The case evokes the 2012 gang rape and murder of a 23-year-old physical therapy student on a bus, which triggered nationwide protests and led to more robust laws ag...