At 8:44am police were called to an address on Sealand Road, Chester, after reports of a serious assault.
Officers attended the scene to find a man and a woman with serious injuries. Emergency services are currently dealing with the incident.
A woman has been taken to Aintree Hospital via air ambulance and the man has been taken to the Countess of Chester Hospital by paramedics.
Sealand Road has reopened to traffic.
At this stage it is believed to be an isolated incident and enquiries are ongoing.