The Crystal Palace star was subjected to vile, discriminatory abuse on social media, which he then re-posted to show his followers.
West Midlands Police have taken a boy into custody in relation to the abuse, before releasing him under investigation on Monday.
Morgan tweeted in response: “So disgusting. The fact the alleged perpetrator is only 12 is even more sickening. Where are his parents?
“How have they raised a child to spew such vile bigotry & hatred?
“As for those hand-wringing about a 12yr-old being arrested, get a grip. He needs a bloody sharp lesson.”
Zaha had posted screenshots of the abuse he had received onto his Twitter account prior to Palace’s 2-1 defeat to Aston Villa on Saturday.
“Woke up to this today,” he wrote, accompanying the images which included threats and references to the Ku Klux Klan.
Crystal Palace tweeted in support of their player, while manager Roy Hodgson also praised Zaha after the match for going public with the “cowardly and despicable abuse”.
Match of the Day presenter Gary Lineker called for criminal punishment for the offender prior to learning of his age, at which point he backtracked.
“12 years old! This kid needs educating, not incarcerating,” he said.
Zaha, 27, has since tweeted his own response, thanking fans for their support and the police for making the arrest.
“People need to understand that whatever your age, that your behaviour and your words come with consequences and you cannot hide behind social media.
“It is important social media platforms do what they did yesterday and seek out these individuals and remove them.
“I want to thank everyone for the love and support but enough is enough.
“It is not enough to be disgusted by these messages I received and move on.
“It isn’t enough to just say no to racism. We need action, we need education, things need to change.”
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