The FBI calls it "a ruthless criminal organisation" which deals in "guns, drugs, and death". The Justice Department holds members responsible for "assault, extortion, insurance fraud, money-laundering, murder, vehicle theft, witness intimidation and weapons violations". But it turns out that one of America's most notorious biker gangs is also pretty handy at DIY.
Police in California have arrested 30 members of the Vagos Motorcycle Club, a group of 300 Harley-Davidson riders, amid allegations that they have been attempting to use home-made booby traps to maim and kill the detectives who keep an eye on their nefarious daily activities.
In recent weeks, a series of potentially deadly devices, built largely from materials bought at local hardware stores, were discovered at the homes and workplaces of a police gang-enforcement unit in Hemet, a suburban town in Riverside County, on the eastern fringes of Los Angeles. The Vagos gang, also known as "The Green Nation", is suspected of planting them.
One contraption consisted of a natural-gas pipeline which was shoved through a hole drilled into the roof of a police gang unit's headquarters. It filled the building with highly-flammable vapour which, in the words of an officer quoted by local reporters, "would have taken out half a city block" if they had not smelled the danger before anyone was hurt.
Another, set at the same location, saw a rifle rigged up so that it would go off when anyone tried to enter the security gate outside. An officer triggered the mechanism, firing a bullet that missed his face by eight inches. He survived unscathed, he said, only because he had moved out of the way to open the gate, which had wonky wheels. In a third assassination attempt, Vagos members are suspected of attaching an explosive device to the underside of a policeman's car as he shopped at a local convenience store. He escaped without injury because he noticed that his vehicle had been tampered with.
No one knows why the mostly Hispanic gang, which was founded in nearby San Bernardino in the 1960s, might suddenly have declared war on police, but there is speculation that the attacks are retaliation for detectives turning up uninvited at the December funeral of a member.
Either way, on Wednesday morning, the police struck back. In scenes straight out of a Marlon Brando movie, cops launched dawn raids on the group at addresses across southern California. They seized large quantities of weapons and drugs, and also discovered a methamphetamine laboratory.
"In the last few months, they've gotten our attention, but today we gave them some attention back," Riverside County's District Attorney, Rod Pacheco, said afterwards.
The high-profile arrests, and revelations about the attacks which prompted them, have raised concerns about biker gangs, part of a sub-culture which began in California during the late 1940s, and was subsequently exported across the world.
Members of the Vagos, who wear green bandanas and leather jackets embroidered with pictures of Loki, the Norse god of mischief, are, as with most biker gangs, suspected of drug-smuggling and running protection rackets. Their territory extends across Mexico and America's south-western states. They have a loose alliance with the Mongols and Bandidos, two other mostly Hispanic organisations, and in the past have chiefly made headlines for sporadic clashes with the Hells Angels, which was also founded in San Bernardino.
The State of California has offered a $200,000 (£133,000) reward to anyone willing to testify against the group. "It's terrible and unprecedented for police officers to be subjected to these kind of terrorist attacks," said the State Attorney General Jerry Brown.