In Kuta, the bars were full, the music loud. Then came a blinding flash and the fireball...

The nightmare began just after 11pm on Saturday, when the bars and nightclubs of Kuta Beach, Bali's brashest and liveliest nightlife area, were heaving with revellers.

One small bomb went off in Paddy's Irish Pub, on Kuta's main Legian Street. A few seconds later a massive explosion ripped through the Sari Club, a nightclub on the opposite side of the street.

The force of the blast knocked people to the ground, hurled bodies through the air and caused a fireball ­ apparently created by exploding gas cylinders ­ that engulfed neighbouring buildings.

The wooden walls of the Sari Club collapsed like playing cards; the flimsy roof caved in, trapping terrified revellers. Those who got out met a wall of flames ­ a line of blazing cars and motorbikes that blocked their exit.

"It was like the sky fell down. There was a blinding white light," Amos Libby, an American tourist, who was unhurt, said. "It lifted me off my feet."

Matt Noyce, a tourist from London, said: "There was complete panic, with people diving for the door and scrambling over each other. Outside it was awful. There were bodies everywhere."

Bruce Baker, from Queensland, said: "There was some poor bugger lying in a corner of the club and one of his legs was gone. He was quite coherent, he was just saying, 'What's going to happen to me?'"

Among other Britons who witnessed the carnage was the round-the-world tourist James Woodley, who was standing on the dance floor when he heard the explosion.

Mr Woodley, whose face had to be bandaged, said: "I heard what I thought was a gunshot outside, I saw people running. And the next thing there was just the most incredible explosion and the whole place had collapsed. I was lying on the floor. I somehow saw a gap, above where I was lying, and I just managed to crawl through a hole. I came out ­ there were flames everywhere. The heat was incredible. I just ran across the top of all the iron, and there was burning bamboo and burning straw. It was just horrific. I had gone on to the dance floor right in the middle of the club, about 20 seconds before it blew up."

Hanabeth Luke, 22, from England, was mourning her boyfriend, a mechanic, who she believes was killed as the two danced at the Sari.

"I was dancing to Eminem, enjoying the flow, when I heard the first bang. Many people stood still, then there was the second. It was an incredible force of wind and heat. Somehow I managed to climb out through the roof. I was in the street in a complete daze, yelling out my boyfriend's name, but I had a strong feeling that he was dead," she said.

Ahmad Zabadne, from north London, felt "extremely lucky" to escape being badly injured along with a group of British friends who were at the bar.

Mr Zabadne, 24, a sales representative, suffered a perforated eardrum in the blast which he fears may leave him without hearing on his left side. "We were in a bar when we heard a huge bang and people started running everywhere. There was about two seconds and then there was another bomb. We were extremely lucky. If we had been further into the bar or further out, we would have been caught in it," he said.

Many survivors fled bleeding and burnt. Some managed to scale a 10ft brick wall at the back of the club. Outside they staggered around, as if in a trance, searching for friends. People lay on the pavement, some with limbs blown off. Many bodies were decapitated.

"There was a procession of people covered in blood, covered in glass," said Richard Poore, a New Zealand television director who was filming outside. "There were people with glass shards embedded in them. There were women with their hair on fire and their bodies on fire. It was horrible."

Bali's emergency services could not cope. Ambulances struggled to ferry the injured to Sanglah Hospital, 10 miles away in the capital, Denpasar. Many victims, half-naked and moaning, were transported by local residents on the backs of mopeds, having been carried to safety by friends.

At the white-tiled mortuary of the hospital, every corner was covered in bodies. More were stacked along hospital corridors and under sheets in alleyways outside. Most were too charred to be identified.

At Sanglah and Bali's other clinics some 300 survivors, many with severe burns, were brought in for treatment. "People are dying because there's no blood, no bandages, no surgical scalpels," said Maria Jakes, a long-time island resident working as a volunteer.

"We've had to go round all the chemists and buy up all the supplies we can. It's an absolute nightmare. People are lying around bleeding and there's nothing we can do for them."

Martin Lyons, an Australian tourist from Melbourne, was walking from his hotel with friends towards the Sari Club when the second bomb exploded. "We were confronted with masses of people running towards us up the street," he said. "The blood, the smell of burnt skin and the pain they were in, you can't really put that into words."

Karim Ansel, from Paris, was sitting at a restaurant table 100 yards away. "There was a mild explosion, followed three or four seconds later by a very powerful one," he said. "I hurled myself to the ground. As I came out, I saw awful, awful things. One person was covered in blood, another woman was running with her clothes burnt on to her body. A man was dressed only in his underpants and covered in blood, with his shoes in his hands. Other people were just completely traumatised."

Hundreds of survivors grabbed their luggage, fled their hotels and spent the night on the beach. Others spent the night in hotel lobbies.

First light yesterday brought more hellish scenes. The walls and roadway on Legian Street were stained with blood. A leg lay on a roof near the Sari Club. A charred hand was on a pavement. Shoes and sandals were scattered across the road.

All that remained of the club was a black crater surrounded by mangled cars. A dozen neighbouring buildings were gutted. Windows were shattered up to a mile away.

Rescuers picked through the rubble, searching for survivors but finding mainly blackened bodies.

The Indonesian army set up a tent outside Sanglah where bodies were displayed. Tourists stood huddled in corridors, some weeping. A German woman lay on the ground, sobbing repeatedly: "My friends are dead." Sixty-four names, mainly European, were listed on a sign on the wall headed, "Have you seen?" Only four were crossed off.

Among those caught up in the blasts were numerous young Australian sportsmen ­ rugby and Australian rules footballers celebrating the end of the season with a trip to Bali.

Members of Kingsley Football Club, an amateur team in Perth, had spent the evening in the Sari Club. Seven of them were missing. The team coach and other players had climbed to safety.