Japanese high-tech firm Hitachi said Friday its net profit plunged 96.6 percent to 2.9 billion yen ($37 million) in the first quarter, citing the impact of the March 11 earthquake and tsunami. Operating profit slumped 40.8 percent to 52.4 billion yen, and sales were down 0.1 percent at 2.15 trillion yen for the April-June quarter. Like many other Japanese firms, Hitachi -- whose products range from microchips to nuclear power equipment -- reported damage to its production facilities and electricity supply problems after the disaster. \"The operating environment remained harsh, not least because of the catastrophic damage caused by the Great East Japan Earthquake of March 11, and ensuing power supply restrictions, and disruptions to supply chains for parts and components,\" it said in a statement. \"The Hitachi Group suffered damage to a large number of buildings and production facilities,\" it said. All of the plants have since resumed operations, even though output capacity at some was still below pre-quake levels, the company said. While suffering a sizable slump for the first quarter, Hitachi upgraded its half-year forecast, now expecting a net profit of 10 billion yen, up from a break-even for the six months to September. Operating profit for the period is now forecast at 100 billion yen, up from its earlier estimate of 80 billion yen, the company said, leaving its sales forecast unchanged at 4.4 trillion yen. \"Hitachi has revised its forecast for operating income from the previous forecast due to progress with cost cutting, including fixed costs,\" it said, also citing \"concerted group-wide efforts to recover from the disaster\". Citing \"uncertain factors\", however, Hitachi left its earlier forecast for the full year to March 2012 unchanged, still expecting a net profit of 200 billion yen compared to a record 238.87 billion yen last year. \"Uncertain factors include trends in the global economy, especially in the United States, Europe and China, foreign currency fluctuations, and fluctuations in raw materials prices,\" it added.