Flight authorities have arrested a woman upon arrival at the Paris-Charles de Gaulle Airport on Monday after she tried to conceal a child inside a carry-on bag on an Air France flight.

About halfway through the flight, a passenger across the aisle noticed something was moving inside the woman's bag. He alerted the crew who opened the bag and discovered a young girl.

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The woman, who is a French resident, had started an adoption process for the four-year-old Haitian girl. Air France confirmed the incident to Mashable.

The woman was taking the child back to France, but was not allowed to board the second leg of her journey in Istanbul.

The woman then decided to buy another ticket and hide the child in her bag. After boarding, she placed the bag at her feet underneath a blanket. Halfway through the flight, the girl started complaining that she needed to go to the bathroom, and she was discovered.

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Air France said it "requested the presence of the French authorities on the flight's arrival." The carrier also added it "will fully cooperate with the ongoing investigation being conducted by the competent authorities."

The woman has been detained by French police at the Paris airport, while the child remains in the care of French authorities, according to the Air France press office.