Mehdi Masroor Biswas, the Bengaluru ITC executive who allegedly ran the pro-ISIS Twitter handle @ShamiWitness, has been arrested by the Bengaluru police. Here's all we know about the case.

Mehdi Masroor Biswas, the Bengaluru-based ITC executive who allegedly ran the pro-ISIS Twitter handle @ShamiWitness, has been arrested by the Bangalore police. Details of the case first emerged when Britain's Channel 4 ran an exclusive story on Mehdi and pointed out that he had the most popular ISIS Twitter account with close to 17,000 followers and his tweets were getting viewed over 2 lakh times a month.

Twenrty four-year-old Biswas has "confessed" that he was handling the pro-jihad account"@ShamiWitness" and had become "a source of incitement and information" for new ISIS recruits, Karnataka DGP L Pachau told reporters.

Biswas, an engineer working as "manufacturing executive" with ITC Foods for an annual package of Rs 5.3 lakh, was arrested from his rented one-room apartment, Police Commissioner M N Reddi said, adding, he did not resist when e police took him into custody.

When contacted, Nazeeb Arif, Vice President Corporate Communications of ITC LTD, admitted that Biswas was an employee. "We informed Bengaluru police about his employment status as soon as we heard media reports on this issue, and are cooperating with investigators, " Arif said.

As far as Biswas' arrest is concerned, conflicting reports have emerged on how the police managed to track him down. While reports in the New Indian Express and Times of India have pointed out that it was due to his mobile number, another report in the Hiindu says Britain's MI6 security agency helped Indian intelligence.

Another report on NDTV says Mehdi's t-shirt, seen on a blurred picture shared in the Channel 4 report helped the officials in identifying him. All reports have confirmed that Biswas masked his static IP address (which would have helped police in tracing him) and thus it was difficult for the agencies to find him.

The TOI report notes that "the cops eventually reached his doorstep by tracking his mobile phone and on the basis of information from intelligence agencies."

The report notes, "all telephone call traffic between Bengaluru and London was being monitored" after the Channel 4 story broke and later MI6 passed on valuable information to Indian officials.

According to a New Indian Express report, "Biswas's mobile tower and IP (Internet protocol) address helped the police advance in the right direction." The report also notes that initially "the police first went to studio apartment A29 on the basis of the address they found on Biswas's mobile bill" where another man by the name Suresh was living. It appears that Biswas had given an incorrect address on his mobile bill.

So how did the Indian intelligence agencies track down his mobile number in the first place given they had no IP addresses? According to a detailed report on NDTV, the officials decided to hunt his Facebook profile based on the t-shirt that was visible in the blurred picture used in the Channel 4 report.

The NDTV report points out that officials went "through Facebook pages using special software, checking for pictures of people sporting similar tee-shirts."

Given Biswas' Bengali accent and a voice analysis of the Channel 4 recording which indicated that the man was in his 20's, the intelligence officials then further narrowed their area of search. They ignored all results which showed men named Mehdi in senior positions as they knew they were looking for a younger man, adds the report.

In the final list, the officials found that all profiles "showed normal activity except for the one who went by the name Mehdi Masroor Biswas. And it seemed to match all criteria - a Bengali boy in mid-20s, an engineer who was located in Bangalore," points out the NDTV report.

As far as Biswas's terror links are concerned, police say he has more of a virtual presence than any real connection. An Indian Express points out, that Masroor had told them before his arrest that he had lied to Channel 4 and was afraid of being beaten by the police.

One officer told the paper that Masroor was "very emotionally invested in the cause of Islam", and that "the @ShamiWitness account seemed to have become his main cause in life... But he did not take any concrete step to actually join the outfit,"

According to the ToI report, Biswas wanted to be in "the creamy layer of operations" in the ISIS such as recruiting and propaganda rather than actual fighting on the ground. "He introduced himself as a Libyan man living in the UK to his followers and ISIS members following him on Twitter, and never revealed his real identity or location," one officer told the paper.

Meanwhile Biswas' arrest has sparked a war of sorts on Twitter between pro-ISIS accounts and Kurdish fighters who are resisting the group. According to a Hindustan Times report, while some pro-ISIS accounts on Twitter called him "a truthful media hero (and) a freedom of rights analyst," pro-Kurdish accounts "uploaded morphed pictures in which Biswas was seen behind bars, wearing a Christmas hat."

Biswas had supported ISIS atrocities on Kurd women such as rape, beheading, etc, adds the HT report.

According to the Times of India report, Biswas showed his jihadist sympathies on Twitter from early 2011. For now, Biswas had been arrested under Sec 125 of IPC (whoever wages war against the Government of any Asiatic power in alliance or at peace with the Government of India or attempts to wage such war, or abets the waging of such war), Sections 18 and 39 of Unlawful Activities (Prevention) Act and Section 66 of the Information Technology act. He also ran a blog called Shamiwitness which had two blog posts analysing the rise of ISIS in the region.

With PTI inputs