BEIJING-- China on Wednesday launched an anti-dumping probe into optical fiber preform products imported from Japan and the United States, the Ministry of Commerce (MOC) said.

The probe was launched in response to an official application made by domestic preform producers, the ministry said in a statement.

The MOC will investigate whether anti-dumping practices exist, the degree of anti-dumping, and damage to Chinese manufacturers of similar products, it said.

The investigation will end before March 19, 2015 under normal conditions, but may be prolonged until Sept. 19, 2015 under special circumstances, according to the ministry.

Optical fiber preform is a piece of glass used to make optical fiber.