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LONDON - Six people were hurt on Wednesday by the latest in a series of letter bombs, but police said they believed the devices were intended to shock, not kill.
Wednesday's blast at the Driver and Vehicle Licensing Agency (DVLA) in Swansea, was the third in three days aimed at agencies or contractors involved in enforcing traffic rules, leading media to blame disgruntled motorists.
But police stressed there had been no claim of responsibility and were reluctant to ascribe a motive.
The bombs were similar to three others sent in January, one of which bore the name of a jailed animal rights activist.
Police also revealed that another bomb had hit the director of an unspecified company at his home on Saturday. All seven bombs were in padded envelopes.
"These devices do not contain conventional explosives, and although we are still awaiting the results of analysis, indications are that these devices are of a small pyrotechnic nature," said Anton Setchell, the coordinator for domestic extremism of Britain's Association of Chief Police Officers.
"The intention clearly seems to be to cause shock and relatively minor injuries."
One woman was treated for cuts in Wednesday's attack. Three colleagues were sent to hospital with hearing injuries and two others were treated at the scene.
"I was shaken, shocked and frightened," the woman, who was not named, said in a statement.
A man described as the victim of Saturday's attack in southeast England, who gave his name only as Mike, told BBC television he had received the mail bomb at home but now believed it was targeted at his business, which he did not name.
"I just opened the envelope ... I pulled it and -- bang," he said. "Fortunately ... I only got a few minor injuries in the stomach, a bit of ash in the face, and burnt finger and thumb."
A letter bomb exploded on Tuesday at a company that handles mail for a firm that makes traffic regulation devices, injuring two men. On Monday, a woman was injured by a letter bomb at the headquarters of a firm managing London's congestion charge, which bills motorists entering the city centre.
On January 18, two incendiary devices were sent to businesses near Abingdon, central England, one of which exploded, and another was found at a company in Birmingham the following day.
"We have had no contact from any group or organisation claiming responsibility or setting out their reasons or motivations for the course of action that has been taken," Setchell, the police coordinator, said.
"We are at a very early stage of our investigation and I want to keep a completely open mind about the motivations behind these packages."
- REUTERS