Bangladesh authorities say 14 of its nationals deported from Singapore are being held over links to a group blamed for attacking secular writers.
The men were part of a larger group of 26 construction workers who were expelled from Singapore last year for supporting armed jihadist ideology.
Singapore announced the news of the deportations earlier this week.
The city state said they were planning to take part in extremist activities elsewhere and shared jihadist material.
A 27th man believed to be part of the same cell remains in detention in Singapore after he was arrested for attempting to flee, following the arrests of the others.
'Links to ABT'
On Thursday, Bangladeshi police confirmed they had arrested all of the deportees when they first arrived home on 21 December.
They released some after finding no evidence against them, but continued to detain 14 after uncovering links to Ansarullah Bangla Team (ABT), a group that has been blamed for attacks on secular bloggers, authorities said.
The released deportees have been put under police surveillance.
Singapore said members of the group had been contemplating taking part in armed jihad in Middle East as well as in Bangladesh against the government.
The home affairs ministry said in a statement that they had a "significant amount of radical and jihadi-related material" including footage of children training in terror camps and instructions on how to conduct "silent killings".
The city-state has a significant number of South Asian labourers working in its construction industry, and the group was considered the first foreign terror cell caught by authorities.