Maliks Tandoori restaurant in Cookham in Berkshire has been damaged in a suspected arson attack.
Fire at the Indian restaurant, which boasts famous customers including Theresa May and Barbara Windsor, broke out on Tuesday morning last week.
Seven members of staff living above the restaurant had to jump out of windows in the two-storey building before fire crews arrived and a man in his 20s suffered serious leg injuries, while another was treated at the scene for smoke inhalation, according to the BBC.
Thames Valley Police have launched an appeal for information as part of an investigation, having said that the fire was a "deliberate attack with intent to endanger life".
They believe a flammable liquid was poured through the letterbox. No arrests have been made.
Restaurant Malik Ahmed told the Sunday Express: "We don't know if this attack was a personal vendetta against us or someone with a grievance against the business.
"I've been living in Cookham for 20 years and the restaurant has been going since 1999. In all those years we've never had any problems with racist abuse or violence.
"Whoever did this would have known there were people in the building because all the lights were on upstairs."
The restaurant is expected to remain closed for several months.
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