MOSCOW, Russia (AP) — Russia’s highest court on Tuesday shut down one of the country’s oldest and most prominent human rights organisations, the latest move in a relentless crackdown on rights activists, independent media and o pposition supporters.

The Supreme Court’s ruling revoked the legal status of Memorial, an international human rights group that drew international acclaim for its studies of political repression in the Soviet Union.

Memorial is made up of more than 50 smaller groups in Russia and abroad. It was declared a “foreign agent” in 2016 — a label that implies additional government scrutiny and carries strong pejorative connotations that can discredit the targeted organisation. Prosecutors said the group repeatedly failed to identify itself as a foreign agent and tried to conceal the designation.

Memorial has rejected the accusations as politically motivated and vowed to continue its work.

“Of course, nothing is over with this,” Maria Eismont, one of the lawyers that represented the group in court, said after the ruling. “We will appeal, and Memorial will live on with the people — because it’s the people behind it serving this great cause first and foremost. The work will continue.”

During the hearing, prosecutors said that Memorial “creates a false image of the USSR as a terrorist state, whitewashes and rehabilitates Nazi criminals” — accusations dismissed by Memorial.

Pressure on the group has sparked public outrage, with many prominent public figures speaking out in its support. A crowd that gathered in front of the courthouse on Tuesday erupted into chants of “Disgrace!” in response to the ruling. Police detained several people who picketed the courthouse.

Amnesty International described Memorial’s closure as “a blatant attack on civil society that seeks to blur the national memory of state repression. The decision to shut down International Memorial is a grave insult to victims of the Russian Gulag and must be immediately overturned,” Marie Struthers, Amnesty International’s Eastern Europe and Central Asia director, said in a statement.

The Council of Europe’s Secretary General Marija Pejcinovic Buric, said the move was “devastating news for civil society” in Russia and indicated that the country “appears to be moving further away from our common European standards and values”.

“We continue to offer our assistance and expertise, but today marks a dark day for civil society in the Russian Federation,” she said in a statement.

US Ambassador John Sullivan deplored the court’s verdict as “a blatant and tragic attempt to suppress freedom of expression and erase history”.

Memorial’s sister organisation, the Memorial Human Rights Center, is up for closure as well, with a court hearing his morning in Moscow City Court.

Russian authorities in recent months have ratcheted up pressure on rights groups, media outlets and individual journalists, naming dozens as foreign agents. Some were declared “undesirable” — a label that outlaws organisations in Russia — or accused of links to “undesirable” groups. Several were forced to shut down or disband themselves to prevent further prosecution.

On Saturday, authorities blocked the website of OVD-Info — a prominent legal aid group that focuses on political arrests — and urged social media platforms to take down accounts after a court ruled that the website contained materials that “justify actions of extremist and terrorist groups”. The group rejected the charges as politically driven.

OVD-Info condemned the ruling to shut down Memorial.

“Memorial is an institution of national memory about the times of the Great Terror and Soviet repressions,” the group said in a statement.

“To shut down such an institution is to publicly justify (Soviet leader Josef) Stalin’s repressions,” it said. “It is a clear signal both to society and to the elites: ‘Yes, repressions were necessary and useful to the Soviet state in the past, and we need them today as well.’”

On Tuesday, five allies of imprisoned opposition leader Alexei Navalny were taken into custody. Earlier this year, a court in Moscow outlawed Navalny’s organisations — the Foundation for Fighting Corruption and his country-wide network of regional offices — as extremist, exposing their staff members and supporters to prosecution.

One of the five detained activists, Ksenia Fadeyeva, is reportedly facing charges of forming an extremist group. Fadeyeva used to run Navalny’s regional office in the Siberian city of Tomsk, and in last year’s election won a seat in the city legislature.

Another Navalny ally, Lilia Chanysheva, was arrested and jailed in November on similar charges. She used to head Navalny’s office in the Russian region of Bashkortostan and is facing up to 10 years in prison, if convicted.

Navalny himself is serving 2½ years in prison for violating the terms of his probation from a 2014 embezzlement conviction that is widely seen as politically motivated. The politician was arrested in January upon returning from Germany, where he spent five months recovering from a nerve agent poisoning that he blames on the Kremlin — accusations that Russian officials reject.

Most of his top allies have faced prosecution this year on various criminal charges and have left Russia.

Also on Tuesday, another prominent human rights organisation — the Civic Assistance Committee that helps refugees and migrants in Russia — said the authorities were evicting it from an office in Moscow it had been allowed to occupy free of charge for years.

Moscow city officials handed the group a document voiding the agreement allowing the use of the space without compensation and ordered it to leave within a month.

“I link it to the overall trend of destroying civil society in Russia,” Civic Assistance Committee head Svetlana Gannushkina told Mediazona.