Police are currently at the scene at the junction of Bank Gardens in the Horsforth area where they say "a number of people have been seriously injured."
Enquiries remain ongoing into the circumstances around the collision which happened at 2.41am.
A West Yorkshire Police spokesperson said: "Police are currently at the scene of a serious road traffic collision in Broadway, at the junction of Bank Gardens in the Horsforth area of Leeds.
"Officers were called in the early hours of this morning at 2.41am to a collision between a car and a taxi.
"Enquiries are currently on going into the exact circumstances of the incident and a number of people have been seriously injured.
"The road remains closed and is likely to remain so for some time."