Four people were killed in the Bangladeshi city of Chittagong on Friday after police resorted to firing upon a large number of protesters who had gathered to demonstrate against a visit to the country by Indian Prime Minister Narendra Modi.
Police claimed that the group of protesters had attacked a police station in the city.
Dozens were also hurt in the capital Dhaka where police used rubber bullets and teargas in clashes with violent protesters, witnesses said.
In Chittagong, thousands of supporters of a religious group that accuses Modi of alienating minority Muslims in India streamed out of mosques after prayers to register their protest against his visit, police official Rafiqul Islam said.
"We had to fire teargas and rubber bullets to disperse them as they entered a police station and carried out extensive vandalism," he told Reuters, referring to protesters.
He made no mention of police using live rounds. Another police official, Mohammad Alauddin, said a Chittagong hospital had received eight people with gunshot wounds, adding: "Among them four succumbed to their injuries."
He identified the dead as three students and a tailor.
Modi landed in Dhaka on Friday for a two-day visit to celebrate the 50th anniversary of Bangladesh's independence.
After being received by Prime Minister Sheikh Hasina, Modi met opposition and government leaders.
Hundreds of protesters then clashed with police near a large mosque in Dhaka, witness Jahangir Alam said. He said dozens were hurt when police fired rubber bullets and teargas after protesters pelted them with stones and set ablaze motorcycles.
Social media network Facebook and its Messenger app, which are often used to organise protests in the country, appeared to be down in some parts of Bangladesh.
An official from Bangladesh Telecommunication Regulatory Commission declined to comment. A Facebook representative did not immediately respond to questions from Reuters.
