Mumbai/UNI: Mukesh Dhirubhai Ambani, a billionaire businessman and the chairman and managing director of Reliance Industries, received a fresh death threat by email, Mumbai police said on Saturday.

According to the police, Ambani received a 'reminder' in the same mail which demanded a sum of Rs 400 cr earlier this week.

The threat mails this time warned the industrialist of serious consequences for ignoring previous threats.

"Industrialist Mukesh Ambani received two threat emails once again between October 31 and November 1, warning him of serious consequences for ignoring previous emails wherein the person (sender of the mail) had demanded Rs 400 crore," said Mumbai Police.

Police and Mumbai crime branch are probing the matter.