BEIJING - Profits for Chinese chemical producers, automakers and other major industrial companies fell 1.3 percent in the first three months of 2012 from the same period last year, China's statistical authority said Friday.

Total profits for the largest industrial companies, or those with annual revenues above 20 million yuan ($3.17 million), stood at 1.0449 trillion yuan during the first three months, the National Bureau of Statistics said in a statement on its website.

Rising purchase prices, weak sales growth and increasing manufacturing costs caused the profit decline, said He Ping, an official from the NBS.

The statement said that in March alone, industrial profits rose 4.5 percent to 438.9 billion yuan from the same period of last year.

The NBS official attributed the growth to a rebound in production and sales, the weakened impact of price fluctuations and an increase in non-operating revenues during the month.

State-owned and State-controlled enterprises saw their profits fall 12.4 percent from one year earlier to 317.2 billion yuan in the first quarter, while private companies' profits grew 22.4 percent during the same period.

The ferrous metal sector was hit the hardest, with profits slumping by 83.5 percent. The chemical raw materials and product manufacturing industries suffered a 23.1-percent drop in profits.

Profits in the power generation sector, however, increased by 28.3percent. The country's oil and gas exploration industry witnessed a 10.6-percent rise in profits, according to the statement.