A man is recovering after his head was slashed several times during a serious attack in Dalkeith in Midlothian.
The 46-year-old was taken to the Edinburgh Royal Infirmary for treatment, where he received 20 stitches.
The male attacker was possibly wearing a white top and grey jogging bottoms.
Lothian and Borders police said the incident happened about 2115 GMT on Wednesday, in Findlay Place, in the Mayfield area of the town.
A police spokesman said: "This was a vicious assault, and we are appealing for anyone who was in the area of Findlay Place on Wednesday night, who either witnessed the incident, or saw, or heard, anything suspicious, to contact police immediately.
"Anyone else who has information that can assist our inquiries should also get in touch."