LUCKNOW, June 23 -- With the staircase engulfed in smoke and cries for help echoing from inside, firefighters battling the deadly Aliganj blaze found themselves unable to enter through the building's only access route. As rescuers searched for another way in, allegations emerged that a biometric locking system at the entrance may have delayed the escape of those trapped inside.

Among those who lost their lives was 23-year-old Sukhamani, an employee of a 3D animation company functioning from the building. According to his friend Yash, Sukhamani had been working there for the past four years and was among nearly 40 employees at the office.

Yash alleged that the office's main gate was equipped with a thumb-impression scanner for access con...