Police are investigating whether a tragic suicide pact killed two people found dead in a luxury hotel in Edinburgh.

One lead being pursued is that the pair each took deadly cyanide to end their own lives in a bedroom of the five-star Scotsman hotel.

The man and a woman, who are believed to have been from Russia or eastern Europe, were found at 12.15pm on 1 August.

The grim discovery sparked an evacuation of the hotel by the emergency services amid fears of a 'chemical incident.'

Fire-fighters told guests on the sixth floor to get out of their rooms amid reports of a 'horrible smell.'

A Scottish police spokesman refused to rule out cyanide in the couple's deaths. He said: "Whether or not this chemical has been digested or absorbed we don't know yet."

Authorities have yet to reveal the names of the pair, whose bodies were removed from the imposing Scotsman hotel for forensic analysis.

Suicide has not been ruled out at this time.

According to the Herald Scotland, fire-fighters discovered the two victims lying in bed with an open container nearby.

That might explain the smell which troubled other guests and led to police donning special gear to go inside.

Comfort and style: A room at the Scotsman hotel
A room at the Scotsman hotel

Ann Lewis, 48, was staying in the hotel at the same time as the dead couple. She said: "When we went down for breakfast just after nine we smelled something really horrible. It almost smelt like sewage."

A spokesman said:"Both bodies will undergo forensic analysis.

"Scotland Fire and Rescue carried out a robust examination of the hotel room and are satisfied the deaths were isolated to the room only.

"There was, and is, no risk to hotel guests, staff or members of the public in the area surrounding the premises.

"All chemical material of interest to this investigation has now been removed from the hotel with zero traces remaining inside the building."

The chemical drama at the Scotsman comes as thousands of people descend on the Scottish capital for the annual Edinburgh fringe festival, which begins today.