The United Kingdom’s foremost government watchdog on racism has officially launched an investigation into the Labour party’s anti-Semitism problem.

The move, announced Tuesday, is unprecedented in that it focuses an official government inquiry on racism and hate speech into one of the county’s oldest parties, which used to be regarded as mainstream and moderate.

The Equality and Human Rights Commission had for months studied Labour’s spiralling anti-Semitism problem before launching the probe.

The Commission’s investigation will evaluate the Labour Party’s handling of many acts of anti-Semitic discrimination, including those detailed in the dossiers that Campaign Against anti-Semitism, a Jewish community watchdog group, has provided in a number of submissions since July 2018, the Campaign said in a statement.

The Commission, which was created by a Labour government in 2006, is vested with tough powers designed to force organizations to comply with equality and human rights laws.

It may compel the Labour Party to reveal details of its handling of anti-Semitism in recent years, including internal communications such as text messages and e-mails.

“The Labour Party has repeatedly failed to address its own anti-Semitism problem,” Gideon Falter, chief executive of Campaign Against anti-Semitism, said.

Jewish community leaders have said that Labour has developed an institutional anti-Semitism problem following the election in 2015 of Jeremy Corbyn, a far-left politician, to lead the party.

The party has come under fire for harbouring anti-Semitic members and leaders. An inter-parliamentary committee of inquiry has dismissed as unsatisfactory an internal Labour audit that largely cleared the party of anti-Semitism allegations.

Corbyn called Hezbollah and Hamas his friends in 2009. He laid flowers on the graves of Palestinian terrorists in 2015. In 2013, he defended an anti-Semitic mural in London.