The Japan Coast Guard plans to build 11 high-speed patrol vessels that authorities hope would give the force more muscle to hunt down unidentified ships operating off the nation's coasts, officials said Wednesday.

The coast guard is seeking around 10 billion yen from the fiscal 2003 budget to start building the vessels, which will take four years to complete.

Coast guard officials outlined this budget request during a meeting Wednesday morning with legislators of the New Conservative Party, the junior member of the ruling coalition.

At the heart of the buildup program are three 1,800-ton-class, high-speed, high-performance patrol vessels that would be equipped with 40-mm canons that officials say can accurately hit moving targets.

Each vessel will also feature a helipad and updated equipment to detect ship movements at night.

Measuring 95 meters in length, the new vessels would be able to cruise at more than 30 knots.

The 40-mm canons would allow coast guard boats to hit but still be outside the range of ships such as the suspected North Korean spy vessel that sank in the East China Sea in December following a shootout with Japan Coast Guard vessels.

Japanese officials say the unidentified ship, which is being salvaged by the government, was armed with long-range weapons, including antitank rockets and heavy machineguns.

The coast guard also plans to build three 770-ton high-speed patrol ships and five special-duty patrol boats that can cruise faster than 40 knots. It currently has four such special-duty patrol boats.