Investigators on Sunday remanded in custody a key suspect linked to last year's deadly cafe siege in the Bangladeshi capital that left 20 civilians dead, police said.

Bangladesh police Saturday said they have arrested an extremist accused of being one of the ‘masterminds’ of last year's deadly siege at a Dhaka cafe where 22 hostages were killed.

A Sydney man was charged on Sunday with committing a terrorist attack and attempted murder that police said seemed to have been inspired by Islamic State, after he repeatedly stabbed a stranger on the street.