New Delhi  - Leading Pakistani human rights activist and former minister Ansar Burney was refused entry into New Delhi and sent back to Dubai by Indian authorities, news reports said Saturday.

Burney, who was human rights minister in the interim government in Pakistan, was sent back Friday night as there was a "look-out notice" - issued in criminal cases and served at entry and exit points in the country - against him, sources told the NDTV network.

Burney who was due to participate in a meet against terrorism to be held at New Delhi's Jama Masjid on Saturday had arrived in the city from London via Dubai.

The incident came as an embarrassment for the Indian establishment as the Pakistani activist has been instrumental in helping New Delhi secure the release of Indian nationals from Pakistani jails.

Some reports suggested it could be a "mistake" at the level of the India's Foreigners Regional Registration Office (FRRO).

The Home Ministry, which said it knew nothing of the incident as well as the notice Saturday, ordered a probe into why Burney was sent back and sought an inquiry from the FRRO, the NDTV report said.

Senior officials however dismissed reports that Burney was deported, and insisted that the Pakistani leader was merely sent back.

Burney, an advisory member of the United Nations Peace Council, played a key role in the release of Indian death row prisoner Kashmir Singh who had languished in Pakistani prisons for 35 years.

He was also working for the release of alleged Indian spy Sarabjit Singh, sentenced to death in connection with 1990 bomb blasts in Lahore and Faisalabad that claimed
14 lives.

"This is the most heartbreaking moment of my life. I cannot understand how the Indian government could deport a person who is relentlessly working for the good of Indian persons lodged in Pakistani jails," Burney told the Times of India daily before he was sent back.

He added he was not given any reason by the immigration officials but was asked to return to Dubai.

"I will continue my efforts in securing the release of Sarabjit Singh and other innocent persons, including Indians lodged in Pakistani jails," he added. (dpa)