"If I'm a robber, how am I going to grow my business? This was an untapped market. "
Similarly, crime figures in San Francisco's Glen Park and Diamond Heights neighborhoods risen far faster this year than the city overall. The two neighboring areas in the Ingleside police district had 20 robberies in the first half of this year, compared with 16 in all of 2005.
Starting in late 2005, police began to notice that robbers were more prevalent and younger - and they had their eyes on high-tech gadgets. Groups of youths as young as 13 or 14 would surround someone and grab the victim's iPod.
"We noticed a significant rise in juvenile crime," said San Francisco Police Capt. John Loftus, who headed the robbery division when the rise in crime started. "I'm not sure if there were more kids or whether they just weren't behaving."
In fact, researchers say the number of teenagers in the population is relatively level.
San Francisco's Canning, who now heads the robbery unit, said there have been cases where young girls were the robbers.
Loftus and other officers speculated that a new generation of gadgetry hitting the streets at the same time might have increased the temptation.
"The iPods came out around this time and wireless became popular. You'd have people sitting in cafes pecking away at $4,000 or $5,000 pieces of equipment. That's a very desirous piece of equipment for a kid to have."
Since the beginning of the year, Canning said his department has recorded robberies involving thefts of 37 iPhones, 122 other cell phones, 100 portable music players and 56 laptops.
The robbers "either keep them or sell them for quick cash," said Canning. "If I steal your $2,000 laptop and get $100 for it, I'm happy."
Statistics show the percentage of robberies involving guns also increased since 2005.
In Oakland, armed robberies are far more prevalent than in San Francisco. In the first five months of 2008, guns were involved in 55 percent of Oakland's robberies, up from 41 percent in 2005. In San Francisco, robberies involving guns climbed from 21 to 25 percent, according to The Chronicle's analysis.
The robbery on a Muni bus at Fifth and Market streets on Aug. 13 was the kind of holdup police report again and again.
Six 17-and-18-year-olds surrounded a man in his 20s as he was preparing to get off the 71-Haight bus at 8:30 in the evening. One of the robbers pulled a gun and demanded his iPod.
The man jumped off the bus and reported the robbery to police at the nearby Powell Street BART station, and the robbers continued riding the bus. BART Police called the San Francisco Police Department, which teamed up with Muni to track down the bus as it headed toward Haight Street. San Francisco officers caught up with the bus on Haight Street, arrested three suspects and detained three others.
The 24 hours beginning at 7:30 p.m. on July 30 show the kind of mayhem facing police on an almost daily basis.
In rapid succession, two purse snatchers violently attacked three women walking separately in the early evening in the Marina in San Francisco. In the first attack, the robbers grabbed a woman's purse and then forced her to the ground. Eight minutes and two blocks later, the robbers did the same thing to another woman, pushing her to the ground in the middle of a street. In the third incident, the robbers' getaway vehicle hit their victim, leaving her with serious head injuries.
Police quickly nabbed two suspects - one of whom admitted committing the crimes, saying he and his accomplice needed money to buy crack cocaine.
Two hours later, near Harrison and 20th streets in the Mission District, two men were shot when they resisted a robbery attempt by another male. One sustained life-threatening injuries - the robber got away.
In the East Bay 6:15 the next morning, two men went on a robbery spree that included five street muggings in Oakland and Emeryville. In one of the robberies, at the Wells Fargo bank on Piedmont Avenue, the assailants allegedly targeted a woman who was eight months pregnant and punched her in the stomach to get her cash. The robbers were nabbed in Berkeley after a witness reported them trying to use a stolen credit card at a gas station.