The mamba bit its breeder, a 30-year-old woman, on Monday, police and media said.
The woman, who had no breeding licence, is in an induced coma at a Prague hospital after receiving an antidote.
Police evacuated her house in the Hlubocepy district in southern Prague while a nearby kindergarten banned children from leaving the premises.
Herpetologists said the snake was unlikely to leave the house given the cold weather outside, but the reptile was found on a tree about 200 metres from its home.
“Mamba found! And caught!” tweeted Miroslav Bobek, head of the Prague zoo whose employee caught the mamba.
“I would like to know when the snake set out on the trip but yesterday’s warm afternoon and a nearly subtropic Friday made it easier,” he added.
The woman who found it in her garden said she was still shocked and added the snake “has had enough” too.
Jokers on social networks used the escape to rename the nearby district of Barrandov “Mambarrandov” and depicted a movie poster with Macaulay Culkin’s head replaced with that of a green mamba to show the snake was “Home Alone”.
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