Two men, including a gay rights activist who worked for the US Agency for International Development, have been stabbed to death in Bangladesh.

Dhaka police officer Mohammed Iqbal identified the activist as Xulhaz Mannan and said he previously worked as a protocol officer for a former US ambassador to Bangladesh.

He said the other victim of Monday's attack was a friend of Mr Mannan's named Tanay Majumder.

Mr Iqbal said Mr Mannan was an editor of Bangladesh's first gay rights magazine, Roopbaan.

The killings occurred two days after unidentified men hacked to death a university professor in a north-western city.

The attack was similar to recent killings of atheist bloggers by radical Islamists in Muslim-majority Bangladesh.