A 19-year-old man suffered serious head injuries after being assaulted with a baseball bat in Leyland last night.
Police were contacted at 10.50pm by the ambulance service after reports that three men had been assaulted on Higher Meadow.
Three men leaving the address were approached by another three men, all carrying baseball bats or similar weapons and demanding money.
The victims retreated back into the house and were followed by the offenders, who ransacked the house and again demanded money.
One of the victims handed over some money, but all three men were then assaulted.
One man was hit over the head with a baseball bat. He was taken to Royal Preston Hospital for treatment and his condition is described as critical.
A 22-year-old man and 21-year-old man were punched in the face and received minor injuries.
DCI Andrea Barrow said: “This is a serious incident in which one man sustained serious injuries. We believe it was a targeted attack but the motive for the incident is unclear at this time.
“I would reassure people that an investigation is underway but the incident has taken place in a densely populated residential area so I would urge anybody that witnessed it, or who has any information that could assist with our investigation, to contact Lancashire Police on 101.”