A gang in balaclavas and high visibility jackets robbed a flat in the west end Glasgow after threatening a 40-year-old man.
The three men entered the flat in Otago Street at about 1050 GMT on Friday. They left after stealing cash.
Strathclyde Police said the victim did not need hospital treatment but was left extremely distressed.
The men ran off towards Great George Street. One of them was of stocky build and was wearing blue Adidas trousers.
Officers have been carrying out door-to-door inquiries and viewing CCTV images.
Det Sgt Kenny McDonald said: "The victim is very upset and distressed by what has happened.
"The incident occurred mid morning and this location is very busy with pedestrians and traffic.
"I would appeal to anyone who may have seen anything untoward or who may have noticed the men in the high visibility jackets following the robbery to please get in touch with us as a matter of urgency."