Four people have been injured in two separate crashes in Co Armagh and Co Tyrone on Thursday 15 August.
The first incident, involving a Suzuki scrambler and Audi A3 Sport TDI, happened at a roundabout in the Lake Street area of Lurgan at around 3.30pm.
Officers attended, alongside colleagues from the Northern Ireland Ambulance Service who provided initial first aid at the scene.
A PSNI spokesperson said: “The passenger of the scrambler, a man aged in his 20s, was taken to hospital for treatment to life-threatening injuries. He remains in a critical condition.
“Meanwhile, the driver of the scrambler also required hospital treatment for serious injuries – whilst the driver of the car sustained minor injuries.
At around 6.15pm emergency services were called to another crash involving a BMW X5 on in the Moy Road area of Dungannon.
The driver of the car, a man aged in his 70s, was taken to hospital for treatment to serious injuries.
He remains in a critical condition.
Police are appealing for information and witnesses to come forward.
They said: “Our investigation is underway and anyone with information about what happened, or who has dash-cam or other footage can contact police on 101.”
