Mehdi, an executive at a company in Bangalore, was exposed by Channel 4 News in a recent report as the owner of the account @ShamiWitness.
The account contained jihadi propaganda as well as information for potential recruits and messages praising dead fighters as martyrs, reports The Guardian.
He also expressed his desire to join the Islamic State if he did not have to take care of his family, "If I had a chance to leave everything and join them I might have."
“May Allah guide, protect, strengthen and expand the Islamic State. It brought peace, autonomy, zero corruption, low crime-rate,” Mehdi wrote last month.
He expressed his support for the Jihadis via Twitter posts. In one of his posts to British fighter Mehdi Hassan, 19, who later died in Kobani, he wrote: “May Allah give you brothers’ decisive victory there.” To another British fighter he said: “May Allah reward you.”
The account was shut down immediately after the Channel 4 report. Indian police told reporters they were investigating the matter, "I have seen the report as you have," Bangalore police commissioner M.N. Reddi said at a media briefing on Friday.
"We have taken note of it and are investigating the matter. We are ready to face any threat perception to the city. We have set up a special team to study the report and trace the culprit," he told The Guardian.
The Islamic State has made wide use of social media for propaganda and recruitment purposes, as well as for distributing execution videos.
Mehdi started as an anti-Assad activist or jihadi analyst but became a radical supporter of Islamic State after the army coup overthrew Egyptian democratically elected President Mohammed Morsi, reports IBT Times.
In an interview with Business Insider, Shami showed his extremely sectarian views: "As sectarian as it may seem, I consider Iran a worse threat to Sunnis as Israel. The only way Iran gets defeated is one project stretching from Beirut to Diyal province [Isis plan]".
Mehdi's transformation from jihadi expert to Islamic State supporter was seen in his Twitter popularity, which rose from 4,700 to 17,770 followers since April 2014.
Twitter service does not monitor content posted by users, but takes action when notified of accounts that violate its rules. While tweeting support for Islamic State is permitted, publishing graphic content is not allowed.