A San Francisco Bay Area man was arrested for allegedly running international sex trafficking websites that included ads featuring children and earned him $21 million.

Wilhan Martono, 46, was arrested Wednesday in Fremont and was being held without bail until he is extradited to Dallas, Texas to face 28 federal charges including conspiracy, money laundering and promotion and facilitation of prostitution, the East Bay Times reported.

It wasn’t clear whether he had an attorney to speak on his behalf.

Martono set up websites allowing users to search for sex workers in more than 14 U.S. cities and on five continents, according to the indictment.

The websites offered various adult prostitution services but some ads featured victims of child trafficking, including a 13-year-old girl who was rescued in Texas last November, the paper said.

The websites used Hong Kong addresses and phone numbers. Payment was made electronically with bitcoins or gift cards, prosecutors said.