Amnesty International says the de facto authorities in Crimea have failed to investigate a series of abductions and torture of their critics since the violence that led to Russia's mostly unrecognized annexation of the peninsula from Ukraine a year ago.

Instead, Amnesty said, Crimea's Russian-backed leaders have cracked down on dissent, creating a climate of fear on the annexed Ukrainian region, with many of the regime's more vocal critics opting to leave.

It cites "violations of the rights to freedom of expression, assembly and association in Crimea [and] highlights human rights abuses by the de facto authorities, including the failure to investigate a series of abductions and torture of their critics, and their unrelenting campaign of intimidation against pro-Ukrainian media, campaigning organizations, Crimean Tatars and other individuals critical of the regime."

Amnesty's fresh report on March 18 comes exactly one year after Russian President Vladimir Putin and Crimean leaders signed a treaty on Crimea joining Russia, a moved widely rejected and condemned by the international community.

"One year on from Crimea’s annexation, the attitude of its de facto authorities and their Russian masters can be summed up simply -- like it or leave or shut up," said John Dalhuisen, Amnesty International’s director for Europe and Central Asia.

Amnesty said since the annexation of the Black Sea peninsula, at least seven people have been abducted, with their fates unknown. At least one other abducted individual has been found dead, with signs of torture.

"Unless the ongoing clampdown on human rights, including freedom of expression, assembly and association in Crimea is reversed, and past violations are effectively addressed, the outlook for the people living on the peninsula is bleak," the group warns in its introduction.

The global human rights watchdog said it has documented the disappearances of three Crimean Tatars.

Islyam Dzhepparov, 19, and Dzhevdet Islyamov, 23, were pushed into a van by four men in black uniform on September 29, 2014, and have not been seen since.

Reshat Ametov, 39, was seized while attending a demonstration in March last year. His body was found later with signs of torture.

Andriy Schekun, the leader of Ukrainian House, an organization promoting Ukrainian language and culture, was abducted by pro-Russian paramilitaries and held for 11 days in a secret location where he was electrocuted in March 2014. He was eventually handed over to the Ukrainian military.

Amnesty said in none of these cases was anyone held accountable.

Amnesty said the de facto authorities are also using intimidation and restrictive laws to silence the media and NGOs.

On January 26, some 30 armed, masked men from a special police unit, accompanied by security officials, raided the offices of the Crimean Tatar TV Channel, ATR, disrupted broadcasting and took away documents dating back to February 2014.

Several journalists and bloggers have fled Crimea, fearing persecution, including the vocally pro-Ukrainian blogger, Elizaveta Bogutskaya.

A number of prominent independent organizations, particularly those working on human rights issues, have ceased to exist.

The Mejlis, which represents the Crimean Tatar community, has been denied recognition and its prominent members subjected to a campaign of harassment and persecution.

The recognized leader of the Crimean Tatar national movement, Mustafa Dzhemilev, told a think tank in Brussels on March 17 that Crimeans “live and survive in fear” and spoke of constant intimidation and searches of schools and mosques for alleged arms and so-called forbidden literature.

He also added that there was “almost zero democratic freedom” and that Russia, through intimidation and blackmailing, is attempting to create “Putin Tatars” responsive to Moscow.

Dzhemilev called for tougher sanctions against Russia.

According to the state-run Russian news agency TASS, Putin will "check the social and economic development of Crimea at a special meeting" with the region's pro-Russian leadership in Moscow on March 18.

Russian presidential spokesman Dmitry Peskov said Putin's "short-term plans did not include a visit to Crimea," although he said the Russian leader may attend a Moscow rally and concert on March 18 to mark the Crimean anniversary.

In a documentary to be aired on Russian TV, Putin said he told senior security officials of his decision to take Crimea just hours after embattled Ukrainian President Viktor Yanukovych abandoned power.

Putin described an emergency Kremlin meeting he said ended about 7 a.m. on February 23, 2014.

Putin said he ordered the military and security agencies to "to save the Ukrainian president's life."

"As we were parting, I told all my colleagues: We will have to start work to return Crimea to Russia," Putin said in the trailer shown on March 8.

Russia annexed Crimea in March 2014 after deploying troops to the region, engineering the takeover of the regional parliament, and staging a referendum denounced by Kyiv and the West as illegitimate.

The Kremlin originally denied that it had sent troops into Crimea, but Putin later said on television that Russian troops had been sent in.

With additional reporting by TASS and Rikard Jozwiak in Belgium