Officers were called to Mirchi Tandoori in the village of Mintlaw, in Aberdeenshire, at 5:35pm on Monday night.
Police later confirmed a man had collapsed in the takeaway and died at the scene.
A police spokesman said: “At 5.35pm on Monday 11 April, police and ambulance attended at commercial premises in Mintlaw, Aberdeenshire to a report of a man having collapsed following a disturbance.
“Sadly the man could not be revived and was pronounced dead at the scene.
“Police Scotland are treating the death as suspicious and have launched an enquiry into the circumstances.
“Enquiries are at an early stage and no details of deceased can be released until next of kin have been contacted.”
All of the windows and the glass panels of the front door were boarded up as police carried out investigations yesterday.
Officers also cordoned off the building which is based on The Square along with the Nisa grocery shop next door.
The village has a population of about 2,700 people and is situated 12 miles away from Fraserburgh in Aberdeenshire.
Scottish footballer Kim Little was raised in the village and her love for the sport started when she played for the local Mintlaw Miracles team as a child.