Image copyright Reuters Image caption Despite being tipped to do well, Eurovision's first punk band PKN were knocked out

Finnish Punk band PKN, the first Eurovision act to all have learning difficulties, have been knocked out of the contest in the first semi-final.

They are one of six entries going home, along with Danish boyband Anti Social Media - the first time Denmark has failed to get to the final since 2007.

Ten acts - Russia, Serbia, Armenia, Belgium, Greece, Estonia, Hungary, Albania, Romania and Georgia - are all through to Saturday's final in Vienna.

Netherlands also made a surprise exit.

Last year their act, The Common Linnets, came second in the contest.

Fans of PKN (Pertti Kurikan Nimipaivat) reacted angrily to news they had not been voted through to the final, after they ranked among early favourites with bookmakers.

George Parry tweeted: "Finland didn't make it through to the #Eurovision final. Tantrum time. #sodisappointed."

Nitin Sood ‏wrote: "PKN made me proud of Finland. Thanks for being amazing, talented and gifted guys. I wish I had your strength and courage."

Image copyright AFP / Getty Image caption Voters were not impressed by Danish boyband Anti Social Media, who are out of Eurovision 2015

Another Eurovision viewer, Matt, tweeted: "Fuming that the Finland entry for #Eurovision didn't get through. 4 guys with learning difficulties giving it their all to rock."

Moldova, Macedonia and Belarus were also knocked out, with another 17 acts set to compete in the second semi-final on Thursday.

The UK's Electro Velvet are one of the "Big Five" acts to automatically qualify for a place in Saturday's final at Vienna's Wiener Stadthalle - along with Italy, Spain, France and Germany.

This year, long-time Eurovision fans Australia will also go straight through as a wildcard entry, competing for the first time with their act Guy Sebastian to celebrate the song contest's 60th anniversary.

Image copyright EPA Image caption Electro Velvet are this year's UK entry

Last year's winner Conchita Wurst - who earned host country Austria an automatic place after storming to victory in Copenhagen - opened the semi-final with a performance of Rise Like A Phoenix, before switching to her other role hosting this year's green room.

The songwriter behind Wurst's winning track has written Serbia's entry this year - Beauty Never Lies, performed by Bojana Stamenov.

After Russia's act was widely booed in Denmark last year, this year's entry Polina Gagarina - who is singing a song about unity, fairness and equality - received a warm reception.

Votes from viewers in all 16 countries appearing in last night's semi-final made up 50% of the acts' total scores, with the other half supplied by professional juries.

The second semi-final is on BBC Three at 20:00 BST on 21 May. The grand final, hosted by Graham Norton, will air on BBC One at 20:00 BST on 23 May.