A young American woman on a European trip was taken into custody after she allegedly threw a newborn out of a hotel window in Paris, killing the baby, authorities said on Tuesday.

The baby was reportedly thrown from a second-floor window of a hotel on Monday morning, according to the Paris prosecutor.

Emergency responders rushed the newborn to the hospital, but the child was pronounced dead.

The mother was travelling through Europe from the US with a group of young adults. She was taken to a hospital for medical treatment following childbirth and has been placed in custody there, officials said.

The child protection police unit has been tasked with investigating the case as a homicide of a minor under 15 years old.

Authorities are considering the possibility of pregnancy denial, a condition in which a woman remains unaware of or in denial about her pregnancy until labour.