KUALA LUMPUR, March 16 (Xinhuanet) -- Malaysian Deputy Prime Minister Najib Razak has said Malaysia, Indonesia and Singapore are increasing the frequency of patrolling in the Straits of Malacca following a spate of pirate attacks.

    "We are doing the best that we can," he told reporters after receiving 5.2 million ringgit (1.36 million US dollars) contributions for victims of the Indian Ocean tsunami at the Defense Ministry Wednesday.

    Najib, who is Defense Minister, said the littoral states could not stop pirate attacks completely due to the long coastline and insufficient ships.

    He was asked on the kidnapping of three crew members of a Japanese-owned tugboat by pirates in the straits on Monday.

    The tugboat's Japanese captain Nobuo Inoue, 56, chief engineer Shunji Kuroda, 50, and Filipino engineer Edgardo Sadang, 31, were abducted by 15 armed pirates who attacked the 323-ton Idaten ownedby Kondo Kaiji Co, a shipping company in Kitakyushu, Fukuoka prefecture, in Japan.

    Najib said the pirates had not made any contact yet to present their demands and Malaysia was very concerned about the incident.

    On the proposal by Japan to send its coast guard to help patrolthe straits, the Deputy Prime Minister said the responsibility to protect shipping in the straits was that of the littoral states, but "we are willing to discuss whatever is appropriate in terms ofthe level of cooperation and the type of cooperation with other countries."

    Last Saturday, 35 pirates armed with machine guns and rocket launchers stormed a oil tanker which was on its way from Samirindain Kalimantan to Belawan in Sumatra. The captain and chief engineer were abducted.

    On March 2, four men in a fishing boat kidnapped a tugboat captain and his Indonesian chief officer.

    The Straits of Malacca is one of the busiest shipping lanes in the world with an estimated 50,000 vessels carrying all types cargoes using it annually. Enditem