Two bombs have exploded in a market in central Indonesia, killing at least 19 people and wounding 20, police said.
The blasts happened in the town of Tentena, on the island of Sulawesi, about 60km (37 miles) from the coastal town of Poso.
Hundreds of people have been killed in violent clashes between Muslims and Christians that first broke out on the island in 1998.
A peace deal was agreed in 2001, but sporadic violence has continued.
Two police officers were reportedly among those wounded in the Saturday morning bombs, which took place about 15 minutes apart in a crowded area.
"The market was packed. It lies in the heart of the town. Victims have been taken to hospital," one listener told El Shinta, a local radio station.
Background of violence
Tentena is a predominantly Christian town that has in the past acquired a reputation as being a dangerous area for Muslims, reports the BBC's Tim Johnston in Bali.
However, there have been tentative attempts at reconciliation over recent months, our correspondent says.
There is no clear evidence that religious tensions were behind the blasts. Police say they are still investigating.
Two bombs exploded in Poso last month but there were no injuries and only minimal damage.
At the beginning of the year, security forces found 60 homemade bombs stashed in an empty house in the town.
On Thursday, the United States sealed all of its four diplomatic missions in Indonesia because of a security threat.
More than 80% of Indonesians are Muslim but in certain parts of the country, such as central Sulawesi, there are similar numbers of Christians and Muslims.