The pitched battle over the European Games

Images such as these in protest of Azerbaijan's human rights record have been widely shared under the hashtag #Baku2015 - originally meant to promote the European Games

The European Games kicks off in Baku, capital of Azerbaijan, on Friday. It's the first Olympic-style sporting festival for the continent - but a hashtag first used by organisers and originally meant to celebrate the games has been turned on its head by human rights campaigners.

#Baku2015 has been tweeted nearly 100,000 times in the last month. It was initially used back in 2012 after the European Olympic Committees launched the new tournament and named Baku as the first host city.

But in recent days, amidst athlete interviews and pictures of Baku's new stadium, a significant number of the most repeated messages are from activists and groups such as Human Rights Watch, PEN and Amnesty International. They're using the tag to detail something very different: the arrests of journalists and the arbitrary detention of activists.

"Ask your leaders to take action to release political prisoners," tweeted the International Federation for Human Rights (known by its French acronym FIDH) along with pictures contrasting the shiny main stadium - named the Olympic Stadium - with a man apparently being led away by police:

Other hashtags including #EuropeanGames and #RealBaku have been tweeted thousands of times by activists, who have also shared cartoons and statistics about political prisoners and jailed journalists.

BBC Trending asked the Azeri government for comment on several accusations, including the widely retweeted complaint from Amnesty International that its monitors were not allowed in the country in advance of the start of the games. "It would be best this visit is postponed, not cancelled, to a later date after the European Games," according to a statement from the Azerbaijani embassy in London. In a separate statement Thursday morning, the embassy called the online campaigns a "well-organised attack" and "totally unacceptable."

"Fundamental rights including the freedom of press and freedom of expression are constitutional rights and guaranteed and protected by the relevant laws of Azerbaijan," the embassy maintained.

Online, government supporters seemed pretty vocal - and co-ordinated - in their attempts to wrest the hashtag back to a discussion about sport. At several points in the run-up to the games, pro-government messages hit Twitter from multiple accounts at roughly the same time:

And the official organising committee and government supporters also tweeted positive images of the Azerbaijani capital, for instance:

Arzu Geybulla, an independent Azeri journalist based in Istanbul, says this pattern is consistent with the way politics works online in the country. The youth branch of the ruling New Azerbaijan Party deploys a number of young people online who call themselves journalists, she says - but actually spread party messages.

The New Azerbaijan Party has been in power for more than two decades - current president Ilham Aliyev succeeded his father in 2003. The government has been criticised by the EU, US, and rights organisations for detaining political prisoners, widespread corruption and election fraud. Human Rights Watch says Azerbaijan "is experiencing one of its worst human rights crises in over two decades since its independence" and that the government is in the midst of a "relentless and systematic crackdown" against its critics - a view supported by the UN.

In April, the European Olympic Committees said in a statement: "It is not the EOC's place to challenge or pass judgment on the legal or political processes of a sovereign nation and, like all sports organisations, we must operate within existing political contexts."

Reporting by Leyla Najafli

Blog by Mike Wendling

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