Nairobi, Sep 30 (DPA) Somali pirates have seized a Panama-flagged ship and its 15 Indian crew members, a group which monitors marine activity off the coast of Somalia said Wednesday.

Ecoterra International said the MT Asphalt Venture was seized in the Indian Ocean early Wednesday morning on its way from the Kenyan port of Mombasa to Durban, South Africa.

"Information... says a pirate group from Brava had captured the vessel and is heading towards Harardheere at the Central Somali Indian Ocean coast," the group said in a statement.

In a related incident, the European Union's anti-piracy force off Somalia said it freed an Iranian-flagged dhow from pirate hands.

Italian warship ITS Libeccio tracked the dhow, which Somali pirates seized off the coast of Tanzania Tuesday, and fired warning shots from her helicopter, EU NAVFOR said in a statement.

The 10 pirates on board agreed to surrender Wednesday morning, EU NAVFOR said. Seven crew members were freed.

Piracy is rife off the Horn of Africa nation, which has not had a functioning central government since 1991.

Attempts to stop pirates taking to the sea in search of ransom - including the deployment of dozens of international warships - have gained only limited success.

Dozens of pirates have been arrested - including one ringleader who was sentenced to death this week by a court in Somalia's breakaway region of Puntland. However, Somalia has no shortage of impoverished young men eager to step in and replace those arrested.

According to Ecoterra International, around two dozen ships and over 400 crew members are being held by pirates.