No arrests have been made after both died at the scene, on Chippenham Road in west London.
A woman has been stabbed to death and a man killed after being hit by a vehicle in west London.
The woman was stabbed in Chippenham Road, in Maida Vale, just after 09:00 GMT, the Metropolitan Police said.
When officers arrived to reports of the stabbing, they also found a man had been hit by a vehicle. Both died at the scene.
No arrests have been made and police said they did not believe there was a wider threat to the community.
Chippenham Road, Elgin Avenue and Goldney Street have been cordoned off.
Eyewitness Mulugeta Asseratte said he was “coming up from the bakery to Chippenham Road and suddenly heard shouts of ‘stop it, stop it’ and it was a girl being attacked by a gentleman”.
“All of a sudden, it moved to the street and no sooner than they reached the street than a driver came and hit both of them.
“We were all shocked and shouting and my heart goes out to the families.”
Police are working to inform the woman and man’s families and post-mortem examinations will take place.
‘Must avoid speculation’
Det Ch Insp Neil Smithson said: “This morning an incredibly serious incident has unfolded in the Westminster area, which has seen two people pronounced dead.
“Our officers are on scene and are working to establish exactly what has happened.
“As soon as we have more information we will keep the public updated but for now we must avoid speculation and allow investigators to do their work.
“What I can say at this time is that the incident is contained.”
Anyone with information is urged to contact police.
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