Crew of Danish ship missing after pirate attack

The owner of a Danish cargo ship that was attacked by suspected pirates in the Gulf of Aden says naval troops who boarded the vessel found no trace of the six-man crew.
Claus Bech, who heads the Shipcraft shipping company, says the M/V Leopard came under fire Wednesday from pirates approaching in two skiffs. Since then, there's been no contact with the crew _ four Filipinos and two Danes.
Bech says "naval forces" boarded the vessel Thursday but found no one aboard. He didn't give the nationality of the troops.
In Friday's statement Bech said the company is in touch with "relevant authorities" to ensure the safe return of the crew, but there's no "reliable information" about their whereabouts.
The Gulf of Aden, between Yemen and Somalia, has been the site of many attacks by Somali pirates.