A 31-year-old man is being treated in hospital after being slashed on the face in the east end of Glasgow.
The man was attacked while fishing with two friends at a pond known locally as "the puddle", near to Gartloch Road, Easterhouse, at 2145 BST on Tuesday.
He is currently in stable condition in Monklands General Hospital.
The suspect was white, aged between 20 to 30, with a thin build and wore dark clothing, a dark jacket with grey panels, and possibly a baseball cap.
He was last seen making off across a field opposite Gartloch Road, in the general direction of Balcurvie Road, Easterhouse.
Det Con Colin Hailstones, of Strathclyde Police, said: "There appears to be no clear motive for this violent attack and it is vital we trace the man responsible.
"I would appeal to anyone who was in the area last night who may have seen or heard a disturbance at around 2145 hours near to the pond to get in touch with police.
"I would also urge any passing motorists or residents in the area who may have seen a man fitting the description hanging around prior to the attack, or running off afterwards, to contact police."