Emergency services are continuing to search for a 19-year-old man from Preston who has been missing since Sunday.
Michael Brookes was last seen around 2am on Sunday (14 January) in Avenham Park.
Preston Police say he left the park alone.
Riversway, Avenham and Fishergate Hill have been searched extensively since Sunday.
Officers have been supported by the North West Police Underwater Search and Marine Unit, the Environment Agency, Coastguard, Lancashire Fire and Rescue and regional helicopter units.
Michael is described as white, around 5ft 7ins tall, of slim build with short dark hair. He speaks with a Liverpool accent and was last seen wearing black skinny jeans and a black hooded top with a camouflage pattern at the bottom.
Inspector Patrick Worden said: “Michael has been missing for a number of days now and we are very concerned for his welfare.
“Officers, with the support of specialist teams from the region, have conducted searches across the area Michael was last seen and we remain hopeful of finding him.
“If you saw him, or know where he is, please contact us immediately.
“Any information, no matter how small or seemingly insignificant, could prove crucial to our investigation.
“Furthermore, I would urge Michael, if he sees this appeal, to call us to let us know he is safe and well.”
Sadly we have still not found Michael who has now been missing for several days. We cannot thank all our staff and various agencies enough who have searched testing land in horrific weather this week to try to find him. This is what we all do when families need us to ? https://t.co/NAqnv8twm9
— ACC Terry Woods (@ACCWoods) January 19, 2018
Anyone with information can contact police on 101 quoting log reference 0641 of January 14.