Iranian state television says a "terrorist attack" has killed at least three people and wounded several others in the southeastern port city of Chabahar.

The TV reported there were sounds of explosions and shooting in the city on Thursday. Details were sketchy as the situation was still developing.

Chabahar, near Iran's border with Pakistan on the Sea of Oman, is home to a new port recently built and is an economic free zone for the country.

State authorities did not identify who was behind the attack. No militant group immediately claimed responsibility for the attack.