Mumbai, Oct 6 : In a quick operation, Mumbai Police tracked and detained a man, who allegedly issued death threats to billionaire industrialist Mukesh Ambani and his family, from Bihar, officials said here on Thursday. A team of Mumbai Police in coordination with the Bihar Police succeeded in tracing the caller, identified as one Rajesh Kumar Mishra, to Darbhanga. Soon, a team from here rushed to take him into custody. "Acting swiftly in the incident of threat calls to Ambani family, a team of Mumbai Police has detained a person from a block in Darbhanga, Bihar, at midnight with the help of Bihar Police. The team is on way back to Mumbai along with the accused," said an official. The development followed fresh death threats given to the Ambani family, and to blow up their iconic residence Antilia and Sir H.N. Reliance Foundation Hospital in south Mumbai here on Wednesday. The calls were received at the HNRF Hospital's call centre at 12.57 p.m. and at 5.04 p.m. warning to blow up the hospital building, said an official spokesperson. The caller also threatened to take the lives of Mukesh Ambani, his wife Nita Ambani, their children Akash and Anand. Not taking any chances, the hospital lodged a formal complaint with the D.B. Marg Police Station and investigations were immediately launched on Wednesday. The fresh threats come barely five days after the Central government upgraded Mukesh Ambani's security to Z+ from the CRPF, while his wife is already accorded a Y+ cover. This is the second time in 50 days that the Ambanis, Mumbai's premier business family, and their hospital have been targeted with such dire consequences. Earlier on August 15, the hospital - which monitored eight calls with similar threats to eliminate the Ambanis - had informed the Mumbai Police which swung into action and arrested the caller, a 56-year-old man Vishnu V. Bhaumick, apparently of unsound mind, from Borivali suburb. Prior to that, in February 2021, the police had recovered an abandoned SUV with 20 gelatin sticks and a hand-scrawled note threatening to finish off the Ambanis, which sparked off a major nationwide political row. Meanwhile, security has been further tightened for the family, their residence and the hospital in view of the latest threats. /IANS