Tokyo, May 30 - Japan's industrial output in April dropped a seasonally adjusted 2.5 percent from the previous month, ministry of economy, trade and industry said Friday.

It also downgraded the assessment of the production, which is the first time since September 2011, saying it "appears to be flat" compared to the previous month's phrase of "showing upward momentum", reported Xinhua.

The index of output at factories and mines stood at 99.6 against the base of 100 in 2010, the ministry said in a report.

Output by transport equipment makers, including auto manufacturers, was down 3.5 percent, while that by electronic parts and devices makers lost 5.2 percent, according to the report.

Chemical companies and pulp and paper manufacturers saw their production dropping 3.3 percent and 6.9 percent respectively.

The index of industrial shipments declined to 98.0, down 5.0 percent while that of inventories stood at 105.2, down 0.5 percent. (IANS)