A man was stabbed by a passenger in the same taxi in Leeds this morning (Thursday).
Police were called to Nowell Mount, Harehills, following reports the man had been stabbed at 5.15am.
The taxi driver collected the pair from the city centre and drove them to the street, where the attack took place inside the vehicle.
The victim, a 30-year-old man, was taken to hospital.
Police believe the men know each other.
Detetctive Inspector James Entwistle, of Leeds District CID, said: "Although our investigation is still at an early stage, this incident appears to have involved two people who are known to each other.
"We are carrying out enquiries into the incident and would like to hear from anyone who may have seen the suspect leaving the scene."
Enquiries are ongoing to trace the suspect, who was described as Asian and was wearing a dark T-shirt, khaki shorts, black trainers and a baseball cap.
A scene is currently in place at the junction of Harehills Lane and Nowell Mount and the taxi is also under guard at the scene pending forensic examination.
Anyone with information is asked to contact Leeds District CID via 101 quoting log number 238 of July 13.