Two former executives of Hydrogen Technology have been sentenced for manipulating the price of the firm’s cryptocurrency and defrauding investors, the U.S. Department of Justice announced on Tuesday. 

Michael Kane, co-founder and former CEO of Hydrogen was sentenced to three years and nine months in prison, while his co-conspirator, Shane Hampton, a former head of financial engineering at the firm, was sentenced to two years and 11 months, according to the DOJ statement.

The DOJ statement, citing court documents, suggested that Kane and Hampton hired an outside firm, Moonwalkers Trading Ltd. of South Africa, to manipulate the price of Hydro tokens on a cryptocurrency exchange in U.S. The group executed about $7 million in wash trades and placed over $300 million in spoof trades for …