NAIROBI (Reuters) – Pirates seized a US-owned  and Italian-flagged tugboat with 16 crew yesterday in the  latest hijacking in the busy Gulf of Aden waterway, a regional  maritime group said.

Andrew Mwangura, of the Mombasa-based East African  Seafarers’ Assistance Programme, said the crew were believed to  be unharmed on the tugboat, which he added was operated from the  United Arab Emirates.

He said the tugboat was towing two barges at the time of  capture but there were no details on their cargo.

“This incident shows the pirates are becoming more daring  and violent,” Mwangura told Reuters by phone.

NATO alliance officials on board the Portuguese warship NRB  Corte-Real, which is patrolling the Gulf of Aden, said a  distress call came from the MV Buccaneer tugboat but  communications were lost six minutes later. They said 10 of the tugboat’s crew were Italian citizens.

Somali pirates have stepped up attacks in March after a lull  at the start of 2009.

International interest has focused this week on the plight  of an American hostage, Richard Phillips, held by four pirates  on a lifeboat flanked by US naval warships in a high seas  standoff since Wednesday.