Naomi,
// This reminds me of the case of the American tourist killed in London by a 'Norwegian' who turned out to be Somali. The power of the media, eh? //
Except that never happened. The timeline can clearly be seen on the AB thread about the Russell Square attack here.
http://www.theanswerbank.co.uk/News/Question1505978-3.html
The initial report said it was a gang attack, and that quickly changed to an ISIS attack. The first time Norwegian was mentioned, so was Somali. See the links at 11:55. There was no period when anyone was tricked into thinking the attacker was a European Norwegian, it always said a Norweigan passport holder who was a Somali was the man detained.