Japan's industrial output plunged 2 percent in May, posting the fourth consecutive month-on-month decline, the Ministry of International Trade and Industry said in a preliminary report released Monday.

The April production index for mines and factories -- which is compared with the 1995 base year figure of 100 -- came to a seasonally adjusted 96.3, or 11.2 percent, down from a year before, according to the report.

The shipment index for May rose 0.2 percent to a seasonally adjusted 98.5, marking the first increase in four months.

The inventories index fell 1.7 percent to 106.7, while the inventory sales ratio index declined 2.2 percent to a seasonally adjusted 113.5.