The Treasury Department published a list of 18 alleged Russian human rights abusers on Friday, defying Russian threats of retaliation.

The list of Russians subject to financial and travel sanctions was required by legislation passed four months and named after a Russian whistleblower who died in custody. Russian officials warned that they were ready to unveil their own list of 104 blacklisted U.S. officials if the list was made public.

It wasn’t immediately clear if the Obama administration has blacklisted additional Russians but kept their identity secret out of “national security” concerns.