Feature: Indian man's arrest reveals quiet on-going infiltrations by IS in South Asia's heartland

Nasimuddin Mian is a devoted Muslim who offers "namaaz" or prayer five times a day, an Indian to the core of his heart and who condemns terrorism.

He is firm in his stand even about his son Maseuddin, a suspected Islamic State (IS) operative arrested by police of the eastern state of India West Bengal crime department and being grilled by all central investigative agencies.

"I don't know whether he is a terrorist. But if he was connected with any terrorist activities, then as a father I demand his exemplary punishment. Islam doesn't approve of any kind of terrorism and violence," said the 62-year-old man.

People in this small town, 180 km from the state capital Kolkata, are shocked by the news of the arrest of his son, Maseuddin alias Musha, about whom the questions from reporters practically go unanswered.

Musha was arrested earlier this week on a train from the southern state of Tamil Nadul to West Bengal. He was suspected to be an operative of IS's South Asia network which is staging assassinations and terror strikes in Bangladesh.

A knife and an improved rifle were seized from him when he was snatched by Indian security agents in the train in Burdwan, according to media reports.

Nasimuddin owns a two-storey brick house without any cement plaster near the local mosque at Registry Office locality in this small town. He is an assistant to the "imam" (cleric) of the mosque. The man with a wiry beard clad in a sleeveless vest and lungi was preparing to offer "namaaz" at the mosque.

The man informed that he had five sons and Musha was the second one. Musha was actually 28 years old and passed secondary and higher secondary examinations in second divisions.

A district police team first visited his home after Musha's arrest on Tuesday and questioned all the family members. Since then hordes of plain clothes men have visited Nasimuddin's home.

Seven years ago Musha married a local girl Saira Banu, who resided nearby in another locality. After passing out from high school, Musha did not get admitted in the local Shambhunath College but in Surendranath College in central Kolkata, where he gave up studies after staying two years.

"Around five years ago, he left along with his wife. At that time he said he was going to Tamil Nadu to set up a grocery shop. He did not ask for any financial help," said his father.

"Last time he came was around four months ago. Around a fortnight ago he called to say he would come to Labhpur. We hoped he would also come home during Eid," he said.

Police believe it was during Musha's stay in Kolkata when he was indoctrinated in jihadi philosophy and not after he migrated to Tirupur in Tamil Nadu.

Musha first came to know Sheikh Yusuf, a Jamaat-ul-Mujahideen Bangladesh militant now wanted by the National Intelligence Agency for his involvement in the Khagragarh blast in Burdwan in October, 2014 while residing in Kolkata, according to investigators.

Yusuf introduced him to Mohammad Suleiman, another Bangladeshi and an IS terrorist. Through Suleiman, he came to know Safwi Armar, a former resident of Karnataka, a southern Indian state, and founder of Indian Mujahideen but now with IS and based in Syria, according to investigators.

Musha had been working as a recruiter for the IS for sometime and was promised a big role of IS in West Bengal if he could kill one of his neighbors and rape the victim's daughter to prove his loyalty, according to media reports.

But before he could carry out the crime, he was arrested by police along with two of his accomplices who were hired by him to help carry out the killing and raping, said local daily The Telegraph. Endit