SA detectives are calling for help as a man remains in hospital after a suspicious fire broke out in a popular Adelaide Hills restaurant.

Mount Barker detectives are again asking for public help as they continue to investigate a suspicious fire that destroyed a Hahndorf restaurant on Tuesday last week.
The Mount Barker Road restaurant was fully engulfed in flames when emergency services arrived during the night and was completely destroyed by the blaze leaving a damage bill upwards of $2 million.
Police said it was closed when the fire broke out and a 48‑year‑old man from Mount Barker was injured and taken to hospital in a critical condition, where he remains.
Fire Cause Investigators and Mount Barker detectives now want to speak to any diners who attended the restaurant before it closed on Tuesday evening, particularly a group of four people who were turned away from the business at about 7.30pm on the night of the fire.
“These people are not suspects but may be able to assist police with their investigation,” police said in a statement.
The CFS said about 70 firefighters were called to battle the fire that fully engulfed The Mustard Seed restaurant in Hahndorf on Tuesday, about 8.30pm.

About 70 firefighters were called to battle the massive blaze that broke out on Tuesday. Picture: Shannon Romeo/FacebookCFS state duty commander Ben Pettman told ABC radio it took more than an hour to bring the blaze under control and no other properties were damaged in the blaze, the CFS said.
Mount Barker Road was closed between Pine Avenue and Auricht Road while fire crews fought the blaze.
Investigators have called for witnesses who may have seen any “suspicious activity” in the area or anyone who may have CCTV or dash cam footage to contact police.
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