Singh, who knows Asma Jehangir personally, spoke to her and apologised for any inconvenience caused to her by the search.

Asma Jehangir had gone to Delhi to attend a meeting of South Asian Human Rights group which was attended by representatives from countries of the region including former Bangladesh foreign minister Kamal Hossain, his wife Hamida Hossain, eminent human rights activist Sigma Huda and editor of The Daily Star Mahfuz Anam.

It was explained to Asma Jehangir that there was enhanced security enforced in Delhi as the Indian Independence Day nears.

Police had 'barged' into the hotel rooms of the Pakistani rights activist and her delegation and started rummaging their luggage shortly after they had checked into a hotel on Monday.

Soon after the Indian prime minister's apology, the New Delhi police ordered a probe into "the circumstances and nuances" of the incident.

A senior police official said the search was a routine security exercise in hotels and restaurants ahead of Independence Day on August 15 in view of the state of high alert in the national capital.

He said the hotel owner had informed the police that a number of foreigners were staying there.