The 51-year-old woman, who had been in India a week, became lost walking to her hotel in Paharganj, near New Delhi Railway Station on Tuesday night, and approached a group of men to ask for directions.

The men allegedly guided her to a secluded spot and then took turns raping her at knife-point.

Delhi police say they have detained 15 men in connection with the case, though it is unclear how many participated in the assault.

The attack has brought yet more attention to Delhi’s grim reputation for sexual violence. The city was seized by protests when a student was gang-raped and bashed to death on board a bus last December.

But sexual assaults, in particular gang-rapes, are an almost daily occurrence in the megalopolis of 22 million.

Attacks on foreigners are rarer, but generate more media attention, and damage India’s international reputation.

Earlier this month, a Polish woman reported to police she was raped by a taxi driver in Mathura, in Uttar Pradesh. She told police she was drugged and raped and dumped in New Delhi more than 100 kilometres away.

In December, a yoga instructor in the holiday town of Goa was arrested for raping his 25-year-old Dutch student. And earlier in 2013, a 39-year-old Swiss woman was gang-raped and her husband bashed while on a cycling tour in Madhya Pradesh. Six men have been jailed for life for the attack.