Trapped and lying in darkness with 11 fellow miners, one of the men who died in the West Virginia mining disaster wrote a note telling his family that death came gently, it emerged last night.

"Tell all I see them on the other side. It wasn’t bad. I just went to sleep. I love you," wrote Martin Toler Jr., a 51-year-old from the small town of Tallmansville, who had worked as a coal miner since his teens.

Toler's farewell, scrawled unevenly in mis-shapen capital letters, was one several notes believed to have been written by the miners, who barricaded themselves into a corner of the Sago Mine in West Virginia after an explosion blocked their route to surface on January 2.

Twelve out of the 13 men trapped underground succumbed to carbon monoxide poisoning in the 42 hours that it took rescuers to find them. The survivor, Randal McCloy, by far the youngest of the group, is in a critical condition with a collapsed lung and possible brain damage and will start an intensive course of oxygen treatment today.

The tragedy of West Virginia's worst mining disaster since 1968 was exacerbated by mistaken reports, corrected three hours later, that 12 of the miners had survived. The first funerals will take place tomorrow. Flags across West Virginia were ordered flown at half-mast.

Toler's note, signed "JR", was given to Tom Toler, his brother, when he was asked to identify the miner's body in the impromptu morgue set up in a defunct elementary school. "It just shook me up when they gave it to me," said Mr Toler. "I took it to mean that it was written in the final stages."

Interviewed on CNN, Toler's nephew, Randy Toler, said: "I think he wanted to set our minds at ease, that he didn’t suffer, and I just think that God gave him peace at the end."

Mr Toler said that his uncle, "a very jolly, happy person", had probably handed his pen to the other miners so that they could also write notes to their families.

"Coal miners typically don’t carry ink pens, just the section boss does and I’m sure he would have directed them to do that," he said. "I’m sure he probably told them that it didn’t look good and they needed to make peace with their maker."

Ben Hatfield, the chief executive of International Coal Group Inc. which owns the mine, said rescuers had found several notes in the alcove two miles from the mine entrance where the men were found.

As families of the dead men searched for the other notes - one relative said as many as four may exist - doctors treating Mr McCloy said that the 26-year-old, who had worked in the Sago mine for 18 months before the disaster, had been transferred to a hospital in Pittsburgh, Pennsylvania, to begin hyperbaric oxygen treatment.

The treatment aims to reduce carbon monoxide levels in the blood, restore oxygen levels and help fight infections. But doctors told reporters that Mr McCloy's condition had not improved as much as they had hoped and that he may have suffered brain damage. "Certainly Mr. McCloy is going to have a tough course," said Dr. John Prescott. "We just don’t know at this point how things will turn out."

Mr McCloy’s father, Randal McCloy Sr., told The Associated Press that he believed that his son survived because his older collleagues had shared the last of their oxygen with him because he was the youngest, and had two small children at home.

"Those men were like brothers. They took care of each other," he said.

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