FILE PHOTO: Representation of the Bitcoin virtual currency standing on the PC motherboard is seen in this illustration picture, February 3, 2018. REUTERS/Dado Ruvic/Illustration

NEW YORK (Reuters) - Bitcoin dropped below $9,000 on Friday to its lowest level in 3-1/2 weeks on concerns about regulatory clamp down around the world following cases of large thefts of digital currencies.

At 8:24 a.m. (1324 GMT), the biggest and best-known virtual currency was last quoted down 4.19 percent at $8,880.10 on Luxembourg-based Bitstamp exchange.