Islam's father served as a brigadier in the Pakistan Army and Shah Nawaz Khan, who was a major general in the INA led by Subhas Chandra Bose, was his uncle, leading Pakistani defence analyst Ikram Sehgal told.
"One son of Shah Nawaz Khan went with him at the time of Partition, while another, Mahmood Nawaz, stayed on in Pakistan and became a full colonel.
In fact, Mahmood Nawaz went and met his father only after retirement as he could not travel to India while he was in service," Sehgal said, providing details of the new ISI chief's extended family.
Shah Rukh Khan's late mother Lateef Fatima was the adopted daughter of Shah Nawaz Khan, according to the Bollywood star's biography on several websites.
Islam, who was yesterday appointed the new head of the powerful spy agency by Prime Minister Yousuf Raza Gilani, comes from a military family and was born in the garrison city of Rawalpindi. It could not immediately be ascertained whether Islam had ever met Shah Nawaz Khan, who died in 1983.
Shah Nawaz Khan was himself born at Kahuta and served in the British Indian Army during World War II. He was captured when Japanese troops overran Singapore in 1942 and then joined the INA. He subsequently fought alongside Japanese forces against the British in Burma (now Myanmar).
Shah Nawaz Khan was captured by the British and put on trial with other INA officers in 1946. They were convicted for treason but were discharged due to intense pressure from the public.
He later joined the Congress party and was elected to the Lok Sabha four times. Before Islam's appointment as the ISI chief, some media reports had suggested that Bollywood star Saif Ali Khan's uncle Maj Gen Isfandyar Ali Khan Pataudi, a deputy director general in the spy agency, was in the running for the top slot.
However, sources told that Pataudi was never seen as a serious contender for the post of ISI chief.
