TOKYO, April 5 (Xinhua) -- A powerful eruption was again observed at Mount Shinmoe on the southwestern Japanese main island of Kyushu on Thursday, the Japan Meteorological Agency (JMA) said.

According to the JMA, Mt. Shinmoe, which straddles Kagoshima and Miyazaki prefectures, erupted at around 3:31 a.m. local time and was the largest eruption since March 25.

The eruption caused volcanic rocks and ash to spew 5,000 meters into the air and the JMA opted to maintain its alert level at the volcano at 3, on its scale which peaks at 5, which warns of approaching the volcano.

One level higher on the alert level would be an evacuation warning, according to the JMA's scale.

The weather agency also issued a warning for people in the vicinity to on the alert for large flying rocks within three km of the crater and pyroclastic flow within two km of the volcano's crater.

During the eruption on March 25, the 1,421-meter high volcano, located in the Kirishima mountain range, spewed plumes of smoke and volcanic ash around 2,100 meters into the air from its crater, the JMA said.