County Tyrone's Ryan Farquhar is seriously ill after he and Dan Cooper were involved in a high-speed crash in the North West 200 on Thursday evening.
he incident happened at Black Hill on the third lap of the Supertwins race.
Belfast Trust said that the Dungannon rider was seriously ill after suffering chest and pelvic injuries.
Farquhar, 40, was airlifted to the Royal Victoria Hospital in Belfast.
Cooper, 28, from Stroud in Gloucestershire, was taken to Causeway hospital in Coleraine with shoulder injuries. He is in a stable condition.
The race was abandoned following the incident.
The Supertwins race had been held up earlier on Thursday evening because of a suspected oil tank fire at a house fire near Station Corner close to the circuit.
Earlier in the day Nico Mawhinney from Castledawson crashed at the Mill Road roundabout.
He was transported to the Royal Victoria Hospital in Belfast by air ambulance. His injuries were described as not life-threatening.