The 49-year-old Headley, who has been under arrest in the US since October three, had travelled to Chembur and Trombay many a times and filmed the exits and entries of the BARC besides the entry of employees, official sources said here on Sunday.
The terror suspect, who has been charged by the FBI with being part of the conspiracy in 26/11 Mumbai attacks, had also taken video shots of the nuclear installation by hiring a boat from Gateway of India. The rear side of the BARC, located on a hill top, can be seen from the Arabian Sea.
The investigators also comprising officials of National Investigation Agency (NIA), probing the role of Headley and his accomplice Tahawwur Rana in India, suspect that Headley, during his boat ride, may have surveyed the mangroves located near the coastline.
The security around the nuclear installation has been tightened and efforts were on to ensure proper cover in the mangroves located below the BARC, the sources said.
Security of NTPC's cold storage plant in the area was also being reviewed as the security agencies were apprehensive that while filming BARC, Headley may have conducted recce of it as well. The terror suspect was trained by Lashker in clandestine filming of vital installations.
The American-born terror suspect, who was allegedly close to top brass of Lashkar-e-Taiba including Zaki-ur-Rehman Lakhvi and Hafeez Saeed, is also alleged to have carried of surveillance of some Bollywood studios.
LeT has always spoken against the film culture and their first target in Jammu and Kashmir were the cinemas.
The investigators were also trying to ascertain whether he had met any other Bollywood actor other than Rahul Bhat, son of noted filmmaker Mahesh Bhat.
Rahul has been questioned by the NIA officials on two occasions earlier. However, his father -- Mahesh -- says that his son has done his duty in approaching the security agencies and helped them in tracing the trail of Headley.
On the fresh development, the senior Bhatt said, "Rahul never took him (Headley) anywhere..That is fact! Rahul never moves with the Bollywood folks. Neither do I."