Postroom staff at the DVLA had already been warned about the possible dangers lurking in yesterday morning’s mail when the explosion came.

At 9.10am there was a bang that deafened the seven workers in the room as shards of glass exploded out of the A5-sized brown padded envelope. The woman who opened the package, a mother in her 30s, was left with with flash burns and cuts to her hands and three of her colleagues suffered hearing damage.

“I was shaken, shocked and frightened,” she said. “Everybody started running around me and I felt quite calm, but I didn’t really know what had happened.”

It appears that she was the latest victim of a letter bombing campaign that started three weeks earlier.

It had been a similar scene on January 18 when a woman opened the morning post at the laboratory of Orchid Celltech in Abingdon, Oxfordshire. The blast also left her with a cut hand and shock. On the back of the envelope was the name of the sender, “Dr Barry Horne”. The name meant nothing to the employee but was to become a crucial factor in the early police investigation.

Detectives assumed that it was a reference to the notorious animal rights “martyr” who died in 2001 during a prison hunger strike while serving an 18-year sentence for planting explosive devices at animal-testing laboratories.

When similar devices were found on the same day at the headquarters of the Forensic Science Service in Birmingham and LGC Forensics in Oxfordshire, it was assumed that the bombs were the work of animal rights activists. Officers from Thames Valley Police’s Operation Rumble, which targets animal rights activists, knew that letter bombs had been used in previous campaigns.

However, there were significant difference. For a start, the animal rights activist Barry Horne has never been referred to as a doctor. The companies that received the packages specialised in DNA testing, have never previously been threatened by the animal rights movement and have no obvious links to experiments. on animals. Finally, animal rights activists usually admit responsibility for their attacks, using a US-based website within four days of their actions.

The Animal Liberation Front told The Times yesterday that it had no knowledge of the attacks or the companies that had been targeted. Robin Webb, a spokesman for the group, said: “We would never refer to Barry Horne as a doctor and any action linked to him is organised around the anniversary of his death on November 5. There have been previous occasions when animal activists have been blamed as a cover for other people or groups.”

Michael Wingfield, 53, knew nothing of the previous bombs when he picked up the post at his home in Folkestone, Kent, on Saturday morning. He assumed that the envelope addressed to a former security company he had run contained a promotional gift.

“I gave my wife a few of the other letters and I took it out of its bag,” he said. “I opened it and it went ‘bang’. Fortunately I was standing up — I believe that made a big difference. If I had been sitting down it would have gone off in my face. It’s a big possibility that it could have blinded me. There was glass sticking in me, in my face, in my finger and in my stomach. My jumper was like a tea bag, and I got a few bits of glass sticking into me.”

His wife, Rose, suffered a perforated eardrum.

The former soldier has run or worked for a number of security firms providing guards and investigation services to a wide range of companies, including those in the financial sector. But he has no obvious links to animal testing.

On Monday another bomb exploded in the postroom at the headquarters of the out-sourcing group Capita in Victoria, Central London. A woman employee was taken to hospital with minor injuries to her hands and stomach.

Among Capita’s many operations is the running of London’s congestion charge, leading to speculation that it had been sent by a disgruntled motorist. There was no suggestion of a link to the earlier devices.

That theory was strengthened the next day when two men were injured opening the mail at the offices of the accountants Vantis in Woking-ham, Berkshire. The envelope was addressed to Speed Check Services, a leading manufacturer of number-plate recognition systems which uses Vantis as a registered address.

The first suspect was an anonymous vigilante, who will only be identified as Captain Gatso. The “Captain” runs a group that advises drivers on avoiding speeding fines, called Motorists Against Detection. It claims to have damaged 1,000 speed cameras in the past six years. However, it has has never used violence against a person and Captain Gatso insisted: “It’s not me or my group. I condemn it completely. We only damage speed cameras, we don’t damage people. I think it’s a loner, I think it’s a grudge.”

Web counter-culture

- “We are fed up with lining the pockets of police forces and councils as a stealth tax revenue-raising scheme”
Captain Gatso

- “Speed cameras along the length of the M4 between Bristol and Swindon . . . where the hell is the logic in that?”
DJ Mysterious

- “I have one wish: to be the passenger in a Ferrari mooning at the speed cameras doing 170”
Dunc 4

- “Drove 160 miles to my brother’s today. Saw about 25 speed cameras. How many police cars did I see? NONE!”
Tunno

- “Speed cameras are alright, it's the fines are the problem”
Silverfox

- “Every time photo radar is put to a direct popular vote, it loses. Big time”
Richard Diamond

- “Speed cameras are unfair — they detect technical, not safety, violations”
Bigger Birdie

“Sod it! If speed kills, I think we need to put safety cameras on each of the following: the East Coast Main Line, Heathrow airport, Eurostar, all RAF runways, Silverstone, Brand’s Hatch”
Big Richard

Source: various internet forums

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