Bangladesh police have held 24 people for questioning following a bomb attack on a shrine in the city of Sylhet on Monday that killed three people.
About 30 people were injured, some critically, in the explosion
The bomb, which injured around 30, went off during a festival at the shrine of Muslim saint Hazrat Shah Jalal.
A 14-year-old boy and an unidentified man died instantly and another man died later in hospital.
Shrine officials said up to 50,000 devotees had gathered for the three-day Urs Sharif festival.
Police said the explosion was the first act of violence at the 700-year-old shrine in Sylhet, 192 kilometres (120 miles) north-east of the capital, Dhaka.
Soldiers moved in quickly and cordoned off the shrine as panic spread among the devotees.
No one has admitted the attack and authorities have launched an investigation.
By Tuesday, police said activities at the shrine had returned to normal with hundreds of devotees reciting from the Koran and praying.
"The entire town is in a state of shock," teacher Shahadat Hossain told the Reuters news agency.
"We never imagined such things can happen here. This is a holy place."
Doctors have said the death toll may rise as some of the injured are in a critical condition.
Last month, the shrine suffered an attack on its fish - one of the top attractions.
About 500 fish were poisoned in a pond.
Legend says that Hazrat Shah Jalal, who came from Yemen to preach Islam, transformed the evil followers of the local king into fish.
Authorities are still investigating how the tropical fish died last month.
Unexplained explosions are not uncommon in Bangladesh.
A year ago, seven people died when a bomb was thrown at the shrine of another Muslim saint
in north-western Tangail district.
Seventeen people were killed when bombs struck two cinemas in the northern town of Mymensingh in December 2002.
And nine people died in explosions at a concert in Dhaka in April 2001.