One of the Russian reporters who exposed the detention and torture of gay men in Chechnya has gone into hiding amid fears of retribution as the scope of alleged abuse widens.

Both the Kremlin and Chechen government have dismissed “provocative” reports by Novaya Gazeta, which said at least 100 men had been rounded up and jailed at secret prisons on suspicion of being gay.

At least three have been killed, the newspaper said, while other detailed horrific torture and beatings before being released with the threat of relatives carrying out “honour killings”.

Elena Milashina has left her apartment in Moscow and plans to flee Russia after Muslim clerics in Chechnya “announced jihad against all the staff of Novaya Gazeta” over the report, which sparked a global outcry.

She told CNN its offices had received two envelopes filled with white powder following the sermon in Grozny, which was watched by 15,000 people and broadcast on regional television.

“We still don't know what the powder is – we have asked the security forces to check it,” Ms Milashina added. “But all of us, including me, consider this situation is very serious.”

Hundreds protest at Russian embassy over 'gay concentration camps' in Chechnya

The meeting saw clerics adopt a resolution calling for the “instigators” of the reports to be held to account – a statement condemned as an “incitement to massacre journalists.”

The Committee to Protect Journalists said the rally was attended by an adviser to the Chechen President, Adam Shahidov, who called reporters “enemies of our faith and our motherland” and promised “vengeance”.

Nina Ognianova, the group’s Europe and Central Asia coordinator, called for Russian authorities to ensure the safety of reporters.

“Novaya Gazeta reporters have taken enormous risks and have paid the highest price for uncovering human rights abuses and speaking truth to power,” she added.

“They should not fear for their safety because they are doing their job.”

The newspaper’s latest report claims that at least six detention centres are being used to house men abducted on suspicion of being gay, with two identified so far in Argun and Zozin-Jurt.

The European Union’s foreign policy chief, Federica Mogherini, told the Russian government it had a duty to protect the human rights of all of its citizens during her first visit to the country.

People hold a protest outside the Russian Embassy in London, following reports of the torture and murder of gay men in Chechnya on 12 April (Josh Withey)

“Our expectation is that the Russian Federation does its part to protect its own citizens in full respect of human rights principles,” she told a news conference, adding that she had discussed the issue during a meeting with the Russian foreign minister, Sergei Lavrov.

He claimed that officials have not yet seen any information confirming the reports but added that Moscow is concerned about “any human rights violations”.

Vladimir Putin met with Chechen leader Ramzan Kadyrov last week in a public show of support for his ally, who has been in power in the Russian republic for a decade.

The Russian President’s spokesman said the Kremlin has no reason to disbelieve Mr Kadyrov’s denials because no one has publicly come out as a victim.

“We have no reason not to trust the head of the republic until there are actual complaints in this regard, not abstract, anonymous but actual complaints,” Dmitry Peskov added.

Human rights activists said it was unlikely that a gay person would come out publicly in Chechnya because of fear of reprisals against themselves and their families.

A spokesman for Mr Kadyrov claimed there were no gay people in Chechnya while defending the government against the allegations.

“If there were such people in Chechnya, law-enforcement agencies wouldn’t need to have anything to do with them because their relatives would send them somewhere from which there is no returning,” Alvi Karimov said.

LGBT+ rights around the globe Show all 9 1 /9 LGBT+ rights around the globe LGBT+ rights around the globe Russia Russia’s antipathy towards homosexuality has been well established following the efforts of human rights campaigners. However, while it is legal to be homosexual, LGBT couples are offered no protections from discrimination. They are also actively discriminated against by a 2013 law criminalising LGBT “propaganda” allowing the arrest of numerous Russian LGBT activists. AFP/Getty LGBT+ rights around the globe Brunei Brunei recently introduced a law to make sodomy punishable by stoning to death. It was already illegal and punishable by up to 10 years in prison AFP/Getty LGBT+ rights around the globe Mauritania Men who are found having sex with other men face stoning, while lesbians can be imprisoned, under Sharia law. However, the state has reportedly not executed anyone for this ‘crime’ since 1987 Alamy LGBT+ rights around the globe Sudan Both male and female same-sex sexual activity is illegal under Sudanese law. Men can be executed on their third offence, women on their fourth Getty LGBT+ rights around the globe Saudi Arabia Homosexuality and gender realignment is illegal and punishable by death, imprisonment, whipping and chemical castration Getty LGBT+ rights around the globe Yemen The official position within the country is that there are no gays. LGBT inviduals, if discovered by the government, are likely to face intense pressure. Punishments range from flogging to the death penalty Getty LGBT+ rights around the globe Nigeria Both male and female same-sex sexual activity is illegal and in some northern states punishable with death by stoning. This is not a policy enacted across the entire country, although there is a prevalent anti-LGBT agenda pushed by the government. In 2007 a Pew survey established that 97% of the population felt that homosexuality should not be accepted. It is punishable by 14 years in prison Reuters LGBT+ rights around the globe Somalia Homosexuality was established as a crime in 1888 and under new Somali Penal Code established in 1973 homosexual sex can be punishable by three years in prison. A person can be put to death for being a homosexual Reuters LGBT+ rights around the globe Iraq Although same-sex relationships have been decriminalised, much of the population still suffer from intense discrimination. Additionally, in some of the country over-run by the extremist organisation Isis, LGBT individuals can face death by stoning Getty

The Chechen interior ministry dismissed the allegations as an “April fools’ joke”, while the press minister demanded journalists name interviewed victims and apologise for their “filthy provocation”.

Mr Kadyrov later said he had met with the region’s human rights council on Sunday and proclaimed that rights have undergone a “grandiose” improvement.

He accused international organisations of conducting a “massive information attack... using the most unworthy methods, reality is distorted, attempts are being made to blacken our society, lifestyle, traditions and customs”.

The reports have been taken seriously by the UN High Commissioner for Human Rights and prominent international organisations, which have urged the Russian government to investigate as well as protect journalists.

The situation has been the subject of a parliamentary debate, as well as a speech by former Republican presidential candidate Marco Rubio in the US Senate.

“Unfortunately this is not a new reality for those living under the brutal tyranny of the Chechen leader, who, by the way, happens to be a loyal ally of Mr Putin,” he said.

“We should never, ever tolerate human rights violations against any person for their political views, their religious beliefs, or their sexual orientation.