Police want to speak to anyone who witnessed a serious assault that occurred early this morning in the Lower Hutt suburb of Moera.
Police responded to a report of five or six people fighting on Trevethick Grove at around 2.15am.
When police arrived at the scene, they found one man who was unconscious and had lost a lot of blood.
The man has received medical treatment and does not have life-threatening injuries, police said.
At the same time, an 18-year-old man was taken to Hutt Hospital by his friends with critical injuries. He has undergone emergency surgery and is currently in Wellington Hospital.
In a statement Senior Sergeant Martin Todd said initial enquiries indicate there was a party at a Trevethick Grove address the men had attended prior to being assaulted.
Police want to speak with anyone who attended the party or who was in the vicinity of Trevethick Grove, Whites Line West and Ludlam Crescent, Lower Hutt at around 2.15am.
Police also want the area's residents to check their properties for any discarded items that may have been involved in the offending.
Police are continuing to examine the scene at Trevethick Grove today.
Anyone with information about the incident is asked to contact the police either via Crime Stoppers or by calling 105 and quoting file number 211218/4047.