The arrested man, identified as Abhishek Tiwari, 28, of Uttar Pradesh's Unnao but living in Mumbai's Nala Sopara since 2016 and working as a delivery boy with a furniture firm, was not satisfied with his job and his life and wanted to do something big to draw the attention of people towards him, a police officer said.
Deputy Commissioner of Police, Cyber Crime Unit, Anyesh Roy said that they had received a complaint last month from the Delhi CM's office about getting life threats to Kejriwal over email and had launched an enquiry.
During investigation, based on technical analysis of inputs collected regarding origin of e-mail, connected mobile phone and IP logs, teams were rushed to Mumbai and Kanpur for locating the suspected user of the relevant email id, police said.
"The suspect, however, had gone underground and was leaving very few digital footprints. With deep analysis of technical inputs, his location was zeroed to Nala Sopara, Mumbai, a densely populated area. The team in Mumbai searched through hundreds of chawls till the accused was finally nabbed," Roy said.
The DCP said that the accused had also sent an email to a municipal office bearer of a major political party in Mumbai, but "disappointed with the lukewarm response, upped the ante and decided to send threat mails to senior political leaders".
"He sent threatening mails to Delhi's CM. The accused has also sent an email of bomb threat to a national party's headquarters here," he added.
Tiwari is being interrogated and the mobile phone he used to send the emails has been recovered and undergoing cyber forensic analysis, a senior police officer said.
( With inputs from IANS )