Police exchanged gunfire with armed attackers Friday at a restaurant in a diplomatic zone of Dhaka, Bangladesh.
Assailants were throwing grenades at police, a source at the scene said.
“An unknown number of people are trapped,” Gulshan police station duty officer Sayedur Rahman said.
A police bomb disposal unit was on standby to go in.
The U.S. Embassy in Dhaka warned of the situation on Twitter, advising people to shelter in place and noting that a hostage situation had been reported.
The area has been cordoned off, police said.