A masked man smashed a wine bottle and held it against a teenage girl’s face after she disturbed him in the back garden of a house.
The victim confronted the man at about 11.30am on Saturday, February 15, at the back of the house in Eastfield Road, Wollaston.
The man wore black clothes, a hooded top and a balaclava.
A police spokesman said: “When he was spotted by the teenager, he grabbed a wine bottle from a bin, smashed it against a wall and held it up to her face, saying “Don’t tell anyone about this”.
“He then fled the scene, leaving the victim shaken.
“She had slight cuts to her neck and cheek, but did not need hospital treatment.”
The man was about 5ft 6in, medium build and had a local accent.
Witnesses to this incident, or anyone who has any information about it, can call Northamptonshire Police on 101 or information can be given anonymously to Crimestoppers on 0800 555111.