Redwanul Azad Rana, a key militant of banned militant outfit Ansarullah Bangla Team (ABT), who fled to Malaysia to avert arrest over the killing of blogger Ahmed Rajib Haider, continued militant activities there, according to police.

During his stay in Malaysia, Rana was in contact with Ashraful Islam alias Ashraf and radicalised him. Ashraf had been living in Malaysia since 2008, police said.

Ashraf became so radicalised that he agreed to join the Islamic State and the so-called IS jihad in Syria, Mohibul Islam, deputy commissioner of Counter Terrorism and Transnational Crime unit of Dhaka Metropolitan Police, told The Daily Star yesterday.

Although Rana was an organiser of ABT in Bangladesh, he was motivated by Junnun Shikder, a militant suspect who was once arrested by the Detective Branch of police in Bangladesh, he said.

According to police, Junnun is now in Syria.

Both Rana and Ashraf tried to go to the war-torn country from Malaysia but failed as Rana's passport had fake information and Ashraf's passport needed renewal, said Mohibul.

Later, they planned to go to the Philippines, but before they could leave, a team of Malaysian intelligence arrested them earlier this month and deported the two.

On February 20, a CTTC team followed Rana from the airport and arrested him and Ashraf at Uttara. Later, a Dhaka court placed Rana, a death row convict in the blogger Rajib Haider murder case, and his associate on five-day remand each.

Investigators also found Rana's connection with Quazi Mohammad Rezwanul Ahsan Nafis, who had been detained in New York over an alleged bomb plot.

According to CTTC officials, Rana and Nafis were friends while studying in North South University and they had a good communication until Nafis' arrest.

During interrogation, Rana confessed to police that he was aware that Nafis wanted to do something in New York, but he claimed he did not know what exactly Nafis would do, said DC Mohibul.

Nafis went to the US on a student visa in January 2012. He was sentenced to 30 years in prison.

Mohibul said Rana was being quizzed and that they hope to glean more information from him.

Rana, 34, is also a charge-sheeted accused in another case filed for planning to kill an assistant headmaster of Monipur High School in the capital in 2013.

About this, the CTTC official said Rana did not admit to his involvement in any of the cases.

Asked if Rana had any links with Nibras Islam, one of the Gulshan café attackers, who once studied at a Malaysian university, Mohibul said they were yet to find any connection.

Rana went to Malaysia on February 15, 2014, managing a passport where he faked his present and permanent addresses, police said.

Asked how Rana could get a passport with fake information, Mohibul said they were investigating it.

Another CTTC official, who is involved in the investigation, requesting anonymity, told The Daily Star that they had come to know that a broker helped Rana get the passport.

Police were trying to identify the broker, the official added.