Lucknow, May 5 : Anil Dujana, the most-wanted gangster who was killed in an encounter with the UP STF on Thursday, had threatened a key witness in a murder case he had been named in soon after his release on bail, about two weeks ago. In the FIR, filed by Sangeeta Tongar in Gautam Buddha Nagar, she stated, "He (Dujana) had killed my husband in 2012. On April 19, when I, along with a gunner and my brother-in-law, was returning from Surajpur court in Gautam Buddha Nagar, our vehicle was overtaken and Dujana appeared. I thought he was in Ayodhya jail but he was out on bail. He threatened me to stop testifying against him in court. For 11 years, over 230 hearing dates, he had managed to drag the case. My life is in danger. " In the FIR filed by the widow, Dujana was booked under IPC sections 341 (wrongful restraint), 504 (intentional insult and provocation) and 506 (threat to cause death or grievous hurt). Following the FIR, UP STF swung into action to track down the gangster. Dujana was most active in the western UP districts of Noida, Ghaziabad, Muzaffarnagar, Bulandshahr, Meerut, among others. Before 2000, he was involved in the illegal trade of iron and steel TMT bars under the patronage of the Sundar Bhati gang. Later, he fell out with Bhati and aligned himself with another Gautam Buddha Nagar- based gangster Naresh Bhati. Following years of gang war between the two Bhatis as well as police encounters, several top members of both the groups, including Naresh Bhati, who had helped Dujana consolidate his position in west UP, had been killed. In a daring face-off in 2011, Dujana and his associates had attacked Sundar Bhati, currently lodged in Sonbhadra jail, and armed with automatic weapons, had barged into the wedding of Sundar's nephew in Ghaziabad. The shootout that ensued left three gang members of Sundar dead but their prime target managed to flee. ASP Brijesh Singh said, "Dujana had formed his own team later and was connected to most of the notable gangsters of west UP. He was close to Mukim Kala gang of Shamli, Balram Thakur gang of Bulandshahr, and around 50 more gangsters spread across Meerut, Etawah, Noida, Muzaffarnagar, Ghaziabad, Hathras. /IANS