Two women have died following a stabbing in Milton Keynes on Christmas Day, police said.
A dog injured in the incident in Bletchley also died after being taken to the vets.
A man and a teenage boy suffered serious injuries.
A 49-year-old man from Milton Keynes has been arrested on suspicion of murder and attempted murder and remains in custody.
Officers were called to a block of apartments in Santa Cruz Avenue just after 6.30pm on Christmas Day following reports of a stabbing.
The two women, aged 38 and 24, died at the scene, Thames Valley Police said. Their next of kin have been informed.
The injured man and teenage boy were taken to hospital and are both in stable condition.
Police said the parties are known to each other.
Senior investigating officer Detective Chief Inspector Stuart Brangwin said: “Firstly I would like to extend my deepest condolences to the families of the women who have tragically died in this shocking incident.
“We have launched a double murder investigation, which may be concerning to the wider public; however, we have made an arrest and are not looking for anyone else in connection with this incident and the parties are known to each other.”
This breaking news story is being updated and more details will be published shortly.
Please refresh the page for the fullest version.
You can receive breaking news alerts on a smartphone or tablet via the Sky News app. You can also follow us on WhatsApp and subscribe to our YouTube channel to keep up with the latest news.