The United States has urged its citizens in Bangladesh to be alert.
It follows recent information the US has received regarding possible threats to American interests in the country.
The US State Department said it had tightened security at its embassy in the capital, Dhaka, and was imposing travel restrictions on its diplomats there.
An anti-US protest in Dhaka
"American citizens in Bangladesh should remain vigilant particularly in public places frequented by foreigners such as hotels, restaurants, shopping areas, and places of worship," it said in a statement.
It also asked US citizens to register at its embassy in Dhaka to receive updated security information.
Last month, the State Department issued a public statement, warning of specific threats to its embassy and other possible American targets in Bangladesh.
The Bangladeshi Government played down the fears and assured foreigners in the country that everything had been done to assure their safety.
In July 2003, the US embassy in Dhaka said it had received death threats against American officials and citizens in Bangladesh.