Following news last week that the US Department of Justice (DoJ) had begun a price fixing probe into the NAND flash market, Japanese firm Toshiba has been subpoenaed by the DoJ, according to Reuters news service.

Last week SanDisk said it had received grand jury subpoenas. The subpoenas follow a suit on August 31 in a Northern California district court that named 24 companies as defendants in a consumer class action suit.

The complaint alleges that SanDisk and other companies participated in a conspiracy to "fix, raise, maintain or stabilise the pricing of flash memory" and to then conceal their actions, in violation of US state and federal laws.

A probe into price fixing in the DRAM market launched in 2002 imposed fines totaling more than $730m. The firms involved in that included Micron, Infineon, Samsung, Hynix and Elpida.

A probe into the SRAM market is already underway by the US authorities after an investigation started last October.

Toshiba is the second biggest player in the NAND flash market with Samsung the largest firm, holding 46 per cent of the market, according to analyst iSuppli.

Shares in Samsung dropped following news of the investigation, although the firm – and SanDisk - has already said it would cooperate with any investigation.

Other players in the market include Micron Technology, STMicroelectronics and Intel.