The British government has implemented the so-called “Magnitsky list”, blacklisting for entry some 60 Russian officials linked to the death of whistleblowing lawyer Sergei Magnitsky in pretrial detention in 2009, The Sunday Times said.

The United Kingdom’s Foreign Office has forwarded the list to the country’s embassy in Moscow, the newspaper said on Sunday.

The list, originally created by U.S. Senator Benjamin Cardin in 2010, comprises prosecutors, judges, investigators and other Russian officials accused of illegally putting Magnitsky in detention and denying him release or sufficient medical help until his death.

The officials are not banned from entry outright, but embassy staff is to take the list into consideration when reviewing visa applications from them, the report said.

The blacklist’s implementation was not confirmed officially as of Sunday afternoon. The newspaper cited as proof of its existence a mention in a letter from the Minister of State for Immigration, Damian Green, to a British lawmaker.

Russia’s ambassador to the United Kingdom, Alexander Yakovenko, said on Sunday he would demand an explanation on the matter from the Foreign Office.

Magnitsky, who worked for Hermitage Capital, accused Russian tax officials of embezzling $230 million on tax returns through a hijacked firm managed by Hermitage.

He was himself arrested on tax evasion charges his supporters call fabricated and died after 11 months in detention. An official check blamed his death on health problems, but the Kremlin’s human rights council said in 2011 he was severely beaten by prison guards before his death.

No state officials were punished over Magnitsky’s death, and the Investigative Committee is pursuing a posthumous case against him.

The case has generated international backlash, with the United States and several other Western countries currently mulling their own “Magnitsky lists” despite harshly worded objections from the Russian government.