According to AFP, Nur Fazira Saad and Fahmi Alias controversially tied the knot last week in Kedah.
An activist spokeswoman for Sisters in Islam stated: "I don't know why this is allowed in a country like Malaysia... We are talking about a developed country.
"The concern is that this is a child being married off."
The ceremony was approved by both the girl's father and an Islamic court.
The 12-year-old's father justified his decision by saying: "It is better for them to get married rather than doing something improper."
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