Afghan authorities say suicide bombers have killed at least 25 people in a usually peaceful city in southwestern Afghanistan.

Nearly 50 others were wounded in Tuesday's attacks in Zaranj, the capital of Nimroz province. Officials say most of the casualties are civilians.

Police say at least three suicide bombers carried out a series of coordinated attacks in different parts of the city.

There was no immediate claim of responsibility.

Nimroz province borders Iran and Pakistan and is usually peaceful, although it has seen a recent increase in violence.