As iPod sales rise dramatically for online merchants, the music player is contributing to an unexpected rise in robberies across the metropolis, the Los Angeles Times reported on Friday.

Robberies of iPods, top-of-the-line cellphones and other gear are up 34 percent so far this year, accounting for about 1,700 of the city's 8,000 total robberies, said the report.

The Los Angeles Unified School District recorded 141 iPod thefts over the last school year, compared with 41 the year before, district police Lt. William Tant was quoted as saying.

Authorities say that attackers usually confront students walking to school or commuters waiting for buses, forcing them to give up their electronic devices, which can cost 500 dollars or more.

Los Angeles Police Department officials said victims and suspects tend to be young, with the majority of suspects between 18 and 25.

"No one used to report when their lunch money got taken, but if a child comes home without their cellphone or iPod, the family may report it," LAPD Deputy Chief Charlie Beck was quoted as saying.

Authorities believe that the numbers are actually higher because many students do not report the crimes.

"iPods and their clones are becoming a highly desirable item among criminals," Beck said. "They are easy to sell."