"Governor of Paktika province has indicated to our Ambassador that those who are involved in this, based on the arrests made, seems to be Pakistan Taliban. The indication was that they were based from the areas beyond Afghanistan, now this is extremely disturbing for us....
"We will follow this case with laser-like precision because this is something extremely disturbing," the Spokesperson in the External Affairs Ministry said here.
Last week, a renegade Taliban militia, the suicide group of the Islamic Movement of Afghanistan, took responsibility for killing Banerjee, claiming she was an "Indian spy".
"We killed Sushmita Banerjee because she is an Indian spy," the group's spokesman Qari Hamza had told The Daily Beast, the online home of Newsweek magazine.
Banerjee, 49, was married to Afghan businessman Jaanbaz Khan and recently moved back to Afghanistan to live with him.
However, she was killed by militants in eastern Paktika province of Afghanistan earlier this month.
The memoir focused on her life in Afghanistan with her husband and her escape from the militants.
