NEW YORK (WABC) -- As CitiBike expands in New York City, the number of stolen bikes is also growing.
NYPD officials say 476 of the blue rental bikes have been stolen this year, up from 300 in all of 2014.
That's an increase of nearly 60 percent.
Most of the bikes have been stolen in Manhattan.
Officials say most of the bikes are taken when they are not properly locked at the stations.
Citibike is expanding. New access stations are coming to Northwest Brooklyn, the Upper East Side and the Upper West Side of Manhattan. Citibike hopes to roll out 6,000 more bikes by 2017.
The city currently boasts hundreds of rental/return stations, and the attractive blue bikes are available all year round, 24 hours per day.