A Telangana resident was detained by Mumbai Police on Saturday for allegedly sending multiple threatening emails to Reliance Industries’ chairman and managing director, Mukesh Ambani.

Ganesh Ramesh Vanpardhi, 19, has been named as the accused. The police said that he had written letters under Shadab Khan’s identity.

In a string of threatening emails, he first sought a ransom of Rs 20 crore but continued raising the demand to Rs 400 crore, according to the police. His detention by the police has been postponed until November 8.

According to reports, Shadab Khan wrote the first email on October 27 with the subject line, “If you (Ambani) do not give us Rs 20 crore, we will kill you, we have the best shooters in India.”