Three people, including a North South University professor, have been arrested on charges of renting a flat to Gulshan café attackers and withholding tenants' information from the police.

The arrestees are Gias Uddin Ahsan, dean of the private university's School of Health and Life Sciences and owner of the house; his nephew Alam Chowdhury; and manager of the building Mahbubur Rahman Tuhin.

A team of the DMP counterterrorism unit made the arrests at the house on Road-6 in Block-E of Bashundhara Residential Area around 5:00pm yesterday, said a Dhaka Metropolitan Police press release last night.

The release, which described Gias Uddin as acting pro-vice chancellor of NSU, said he did not submit tenants' information to the respective police station.

“Probe has found that the militants gathered at Flat-A/6, House-3, Block-E on Road-6. The associates of the militants rented the flat in May. Following the Gulshan café attack, the associates fled the flat,” read the release. 

A carton loaded with sand and dresses left behind by the militants were also seized from the flat, Masudur Rahman, deputy commissioner (media) of the DMP, told The Daily Star last night.

Police suspect the carton was used for keeping grenades, he said.

Following their arrest, the three were taken to the DB office on Minto Road, said police sources. 

Talking to The Daily Star, a senior DMP official said the Gulshan attackers moved to the flat two days before the café siege.

The NSU professor's nephew Alam Chowdhury negotiated the deal for renting out the flat.

In March, the DMP had announced it had been collecting “identification information” on landlords and tenants since November last year and asked all to provide the information by March 15.

DMP Commissioner Asaduzzaman Miah asked the city dwellers to fill in certain forms and submit those to their local police station.

Talking to The Daily Star on Friday, a top official at the police headquarters said that from now on, it would be considered an offence if owners rented out their houses without proper verification of tenants. “We used to consider it negligence. But now, we will consider it an offence,” he said.

Contacted, NSU VC Professor Atiqul Islam said according to the private university act, NSU's board of trustee has nominated three for the post of pro-VC and Gias Uddin is one of them. The president will pick one.

About the arrest, he said, “I won't make comments without knowing anything for sure.”

An NSU source said Gias Uddin came to the university on Thursday as usual.

On July 1, armed militants attacked the Holey Artisan Bakery in Gulshan's diplomatic zone and killed 20 hostages -- nine Italian, seven Japanese, two Bangladeshis, one Indian and one Bangladesh-born US citizen. Two police officers were also killed.