Officers were called to a property in Church Row, Otley Road, at 8.20am today (June 20) and on arrival found an 11-year-old boy and 40-year-old man with serious injuries believed to be sustained by a bladed article.
Both males were taken to hospital and the road was closed while emergency services attended the property.
DI Steve Menzies, Senior Investigating Officer of the North Yorkshire Police Major Investigation Team, said: “I am relieved to say that following emergency surgery, the 11-year-old boy is now in a stable condition in hospital.
“The 40-year-old man remains in a serious condition and is under police guard.
"Two other children aged 10 and 13, who were also in the house at the time of the incident, are being cared for by relatives and supported by specialist Police Officers.
“I can reassure the public that we are not looking for anyone else in connection with the incident and an investigation is underway to establish the full circumstances of exactly what happened this morning.
“I also want to thank ambulance staff, paramedic teams and police officers who quickly arrived at the scene and administered emergency aid to the injured males."