A man suffered serious facial injuries when he was assaulted by two men in Chorley on Friday.
The attack took place around 7.40am at a business premises on Common Bank Industrial Estate.
The 44-year-old victim was working inside a unit when he has been approached by two men who attacked him with a metal bar.
They then fled into nearby woods and could not be found, despite a large-scale police search which included use of the police helicopter.
The victim was taken to Royal Preston Hospital where he was treated for facial injuries.
Detective Inspector Paul Rudd from Chorley CID said: “This was an unprovoked assault and the motive is still unknown at this time, although we believe this man has been deliberately targeted.
“An investigation is underway but specifically I would appeal to anybody that saw two men stood at the junction of Common Bank Lane and Woodside around 7.30am this morning to contact police.
“I am convinced the area would have been busy at this time with people going to work so I’d appeal to anyone that saw these men to come forward.”
The offenders are both believed to be white and aged in their 20s.
The first man is described as being around 6ft 2inches tall and slim build and the second man was stockier and around 5ft 8ins tall.
Both were wearing dark hooded tops.
Antone with information is asked to call Lancashire Police on 101.