A 67-year-old resident of the block in the Charlottenburg district found the baby which was in a plastic bag, on Sunday morning as he was on his way to buy bread.
A special armed commando team was summoned to arrest a 40-year-old woman, a 15-year-old girl and a 45-year-old man from one of the flats in the block. They were called because the man reportedly has a criminal record for violence.
It is thought the 40-year-old woman had given birth to the baby on Saturday night in the flat where she lived with her teenage daughter. There is no information about whether the arrested man was the father of the baby.
People living nearby have said the woman had tried to hide her pregnancy, although police would not comment on the rumours.
But a police spokesman said his colleagues were sure the baby had been thrown out of the flat. “There are clear signs for that,” he said.
A post-mortem examination will be conducted to determine whether the child was alive when it was thrown from the flat or whether it had died beforehand.