A U.S. nuclear-powered submarine arrived at the U.S. naval base in Sasebo, Nagasaki Prefecture Monday to give a short break to its crew, said reports from the southwestern Japanese port city of Nagasaki.

The submarine "La Jolla", with a displacement of 6,080 tons, came amid widespread concerns in Japan over radioactive leakage by another Los Angeles-class fast attack submarine "Houston" when it called at the port in March.

Dozens of local people rallied near the base, demanding no admittance of the nuclear submarine be allowed to the port until safety is confirmed. "La Jolla, go away," they chorused.

Meanwhile, a sit-in was held in front of the peace memorial statue in Nagasaki City in protest against the submarine's arrival.

On Saturday, the Japanese Foreign Ministry said in a press that the Japanese side was informed that Houston began leaking radioactive substances when it traveled to Sasebo in March during its tour around the Pacific.

The release came after a CNN report, which had been confirmed by the U.S. Navy, revealed Friday that Houston was found leaking traces with radioactivity during a regular checkup in Hawaii in July.

La Jolla visited Sasebo in July 2004, when a small fire broke out onboard, causing no injuries.

(Xinhua News Agency August 4, 2008)