Two men have been injured in an attack involving a Samurai-type sword, North Yorkshire Police have said.
The men were assaulted at a house on Inman Walk, Knaresborough, at about 0030 GMT on New Year's Day.
A 31-year-old man has been arrested in connection with the incident and is being questioned by police.
Police said a 31-year-old man suffered a serious cut to his arm. A 21-year-old man suffered a cut to his face. Both are being treated in hospital.
North Yorkshire Police said while the men's injuries were not considered to be life-threatening, they would require a "significant amount of surgery".
A number of vehicles were also damaged in the incidents.
A force spokesman said the weapon involved was believed to be a two-foot long Samurai-type sword.
He added that it had yet to be found by officers, and anyone who knew where it may be located, or who found it, should contact the force.
Police also want to speak to anyone with information about the incident.