Kelly Mary Fauvrelle, 26, went into cardiac arrest and died despite efforts from paramedics to save her.

Authorities have made arrests in the stabbing death of an eight-months-pregnant woman in what police are calling a "horrific" attack. Her baby was delivered by paramedics, but is in critical condition.

British police were called to a residential address in Croydon, a neighborhood of south London, on Saturday night, where they found a heavily pregnant woman suffering from stab wounds.

The woman, identified as 26-year-old Kelly Mary Fauvrelle, went into cardiac arrest and died despite efforts from paramedics to save her. She is believed to have been around eight months pregnant at the time of her death, according to police.

After paramedics delivered the baby, the child was taken to hospital and is in critical condition, according to London's Metropolitan Police service. The gender of the baby has not been revealed.

A 29-year-old man was arrested on suspicion of murder on Saturday and remains in police custody. A 37-year-old man was also arrested in connection with the attack but has since been released. Police did not provide the names of the two men.

Police said they are keeping an "open mind" about the motive for the attack and have appealed to the public for information.

"This is a horrific incident in which a young mother has lost her life and her child is critically ill," said Detective Chief Inspector Mick Norman.

"At the forefront of our enquiries is understanding what exactly has lead to these tragic circumstances, and we are doing everything we can to establish the facts."

London Mayor Sadiq Khan condemned the attack on Twitter, writing:

"Violence against women has no place in our city, and horrific murders in the home like this show the scale of the problem we face. My heart goes out to this innocent child, and to the mother they have so tragically lost."

On Sunday Croydon police said they were increasing their presence in the area and providing reassurance following the attack.

Forensic and police presence remains in place at the address in Thornton Heath in south London.

A post-mortem examination will be held in due course.