POLICE have arrested a woman suspected of decapitating her new-born baby and dumping the remains in a rubbish bin.

Details of the sickening crime first emerged last week when detectives launched an urgent appeal to find the mother.

Civil Guard officers in Madrid on Tuesday arrested an immigrant who was born in Ecuador.

Reports on Tuesday afternoon said police were searching her house in the working-class Madrid neighbourhood of Vallecas.

The suspect, who has been taken into custody, has not been named but has been described locally as a married woman with children.

In December, authorities discovered a girl’s remains placed in multiple plastic bags at a recycling facility in Madrid. However, they only revealed the investigation to the public last week.

A worker made the traumatising discovery at a garbage plant in Loeches, east of Madrid.

Doctors confirmed the little girl was born alive and was just five days old when she was mutilated and abandoned.

Tests revealed she had been born alive and decapitated with a knife before her body parts were stuffed into garbage bags.

Local cops launched “Operation Natal” in a bid to “get justice” for the dead infant.

They made a plea for help identifying a woman they estimated to be aged around 40 who had been pregnant during the last months of last year.

Last week, a police representative stated: “Based on the current findings, it has been established that the remains belong to a female infant who was born alive.”

“There are indications that would point to her death being of a violent nature.

“We are seeking the public’s help in clarifying this criminal act and asking anyone who could have any information of interest to contact us.”

Detectives were already working on the theory the newborn baby could have been of Latin American origin.

They believe her remains ended up in the Loeches plant after being thrown into a container in the Vallecas neighbourhood close to the M-30 motorway.

A specialist sniffer dog was instrumental in allowing cops to trace where the rubbish came from.

Dylan, a K-9 agent from the Central Cynological Service specialised in detecting biological remains, was brought in to search the piles of rubbish.

He sniffed out several bags containing remains of the newborn.

Investigators tracked the source of that particular trash batch and determined that the bags were discarded at the Loeches facility during the evening of December 12.