A group of Afghan women who braved an enraged mob yesterday to protest against an "abhorrent" new Afghan law had to be rescued by police from a hail of stones and abuse.

The protest by about 200 women, unprecedented in recent Afghanistan history, was directed at the Shia Family Law passed last month by the Afghan parliament which appears to legalise marital rape and child marriage.

The rally, staged by mostly young women with their faces exposed, was a highly inflammatory act of defiance in a country as conservative as Afghanistan. It provoked a furious reaction from local men and a rapidly expanding mob threatened to swamp the demonstrators as they tried to approach the Afghan parliament.

"Go home if your mothers and fathers are Muslims," one Shia cleric shouted at the protesters, who were pressed into an ever-tighter huddle as the crowd surrounded them. "These people will beat you if you stay."

Some of the women appeared cowed by the aggression, staring blankly at the ground, but one shouted back: "If you were Muslims, you wouldn't pass this law." As the protesters continued to chant slogans they were often drowned out by counter chants of Allahu akbar (God is greatest). "I am not afraid. Women have always been oppressed throughout history," Zara, an 18-year-old student, told The Times as men in the crowd lunged forward and screamed abuse.

"This law is against the dignity of women and all the international community opposes it. The US President calls it abhorrent. Don't you see that actually we are the majority?"

The baying mob tore down banners, spat on demonstrators and hurled stones. As police struggled to maintain order, at one point the women appeared to be in danger of disappearing under a sea of shaking fists.

Women police officers drafted in to help to oversee the march attempted to link arms around the female protesters and riot police eventually succeeded in separating the rival groups sufficiently for the march to continue.

Local sources suggested that some of the protesters were members of the Revolutionary Association of the Women of Afghanistan, a secretive women's rights organisation with Maoist origins founded in the 1970s.