Sweden reels after shock suicide bombing in Stockholm

Sweden remained in a state of shock yesterday as police stepped up their investigation into Saturday's potentially devastating "terrorist attack" which caused two explosions to rip through a busy Stockholm shopping district, killing a suspected suicide bomber and injuring two bystanders.

The blasts caused panic among Christmas shoppers in the capital's crowded Drottninggatan shortly before 5pm local time, when a car suddenly blew up. The explosion was followed, within minutes, by a second detonation. Ten minutes earlier a set of emails had warned of the attacks.

"Terrified people were just running in every direction," one eyewitness told the Dagens Nyheter newspaper. "There was a lot of smoke and the smell of gunpowder." Another said the bomber had "shouted something in Arabic" before the explosions. Miraculously the two shoppers hurt in the blasts suffered only minor injuries.

Carl Bildt, Sweden's Foreign Minister, said of the attack: "It could have been truly catastrophic." His view was echoed yesterday by Magnus Ranstorp, a Swedish expert on terrorism, who said all the evidence showed that the bomber could easily have caused a "massacre".

Police said the second explosion killed what appeared to be the suicide bomber. An ambulance crew member said the dead man looked as if he had been carrying a device around his stomach which had exploded. Eyewitnesses said they saw him lying on the ground with blood coming from his abdomen.

Unconfirmed media reports said the bomber had been carrying six pipe bombs. They said the cable connecting the devices had broken, which meant only one of the bombs exploded. The bomber was also said to have been carrying a large quantity of nails in a rucksack. Investigators said the first blast was caused by a gas cylinder which had been detonated inside the car.

Anders Thornberg, a spokesman for Sweden's security police, described the blasts as a "very serious terrorist attack". However he said the authorities did not think there was an acute threat of further attacks. "As far as we know this man was working for himself. We are still trying to find out whether others were involved," Mr Thornberg said.

The emails sent to a Swedish news agency minutes before the blasts threatened attacks on Swedes and criticised the country's 500-man military contingent in Afghanistan. Police said they also contained a link to a voice recording which accused the Swedish Government of waging a war against Islam.

The emails described Lars Vilks, a Swedish artist who in 2007 drew a cartoon of the Prophet Mohammed, as a "pig" and urged all Muslims living in Sweden to "stop sucking up and degrading yourselves". It added: "Now is the time to attack. Do not wait any longer. Come forth with whatever you have even if it is a knife."

Germany's Der Spiegel claimed on its website yesterday to have received information which identified the suicide bomber as a young Iraqi man who was known as a vociferous internet opponent of the wars in Iraq and Afghanistan. The man made his views known on online chat forums. It said the Swedish authorities were also assuming that it was he who sent the emails warning of the attacks minutes before carrying them out.

The attacks have caused widespread consternation and shock in Sweden, a country in which terrorist violence is rare. They have the potential to increase growing public hostility towards the country's Muslim population.