US President Donald Trump says he has signed a full and unconditional pardon for Ross Ulbricht, who operated Silk Road, the dark web marketplace where illegal drugs were sold.

Ulbricht was convicted in 2015 in New York in a narcotics and money-laundering conspiracy and sentenced to life in prison.

Trump championed Ulbricht’s cause, joining libertarians who said the conviction was an example of government overreach. On Tuesday, he said he had called Ulbricht’s mother to inform her that he had granted a pardon to her son.

Silk Road, which was shut down in 2013 after police arrested Ulbricht, sold illegal drugs using Bitcoin, as well as hacking equipmen