The development comes amid a report warning that the mass migration of Rohingyas could pose security risks around the world.
The anti-India LeT may look to recruit the vulnerable Rohingyas through the FIF to mount terrorist attacks.
The Rohingyas are an ethnic Muslim group who constitute around one million of Myanmar's predominantly Buddhist 50 million population.
They speak a Bengali dialect, mainly reside in the country's impoverished northern Rakhine state.
Myanmar views them as illegal Bangladeshi immigrants and doesn't officially recognize them as its citizens, rendering them stateless.
The Rohingyas have allegedly been subjected to human rights abuses by Myanmar.
In an online announcement, Shahid Mahmood, the FIF's head of foreign operations said the organization intended to "start its relief activities in all areas of Burma where Muslims are besieged."
For starters, it distributed million worth of cash and blankets to the refugees.
A senior Bangladeshi intelligence official said the FIF was operating with the local Islamist groups in refugee camps near Cox's Bazaar.
"The FIF's operations could mark a dangerous new phase in the Myanmar conflict," a Bangladeshi intelligence official said.
Reportedly, Dubai and Pakistan-based Rohingya leaders were seeking help and aid from LeT-affiliate Jamaat-ud-Dawah (JuD) to support refugees from the community in Pakistan and India.
Meanwhile, the Belgium-based conflict organization International Crisis Group (ICG) has warned of possible cross-border militant attacks by Rohingyas.
Worryingly, LeT founder Hafiz Saeed has accused India of colluding with Myanmar in the persecution of Rohingyas.
In an unauthenticated video, Saeed reportedly told Rohingyas fleeing Myanmar to 'join jihad' and wage a 'holy war.'
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