Indian immigration authorities refused entry to a former Pakistan human rights minister who helped Indians imprisoned in Pakistani jails, including a convicted spy who spent 18 years on death row, officials said Saturday. Ansar Burney, who served as human rights minister in Pakistan's caretaker government earlier this year, had planned to attend a terrorism conference in New Delhi organized by a local rights group. “This is the most heartbreaking moment in my life ... I can't understand how the Indian government could deport a person who is relentlessly working for the good of Indians lodged in Pakistani jails,” The Times of India newspaper quoted Burney as saying before being deported Friday at New Delhi's airport. Indian media and Burney's local hosts expressed outrage at the authorities' decision. The Home Ministry ordered an investigation into why he had been sent back to Dubai in the United Arab Emirates, from where he had flown to New Delhi, ministry spokesman Onkar Kedia said. In March, Burney successfully petitioned Pakistan President Pervez Musharraf to pardon an Indian man on humanitarian grounds who had spent 35 years in jail for alleged espionage. He also played a key part in getting the execution of a convicted Indian spy, Sarabjit Singh, stayed by the Pakistan government. Singh, who had spent 18 years on death row, was due to be hanged April 1. Pakistan and India have a history of bitter relations.