The leader of the Northern Branch of the Islamic Movement in Israel, Raed Salah, is beginning a nine-month jail sentence for incitement.
Salah was convicted last year over a sermon he delivered in 2007 in Jerusalem in which he uttered an antisemitic blood libel.
"It is an honour to go to prison for the sake of al-Aqsa," Salah declared as he left his home.
UK Labour leader Jeremy Corbyn met Raed Salah in 2011 and called him a "very honoured citizen". Mr Corbyn claimed he had been unaware of any racist attitudes held by Salah.
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