Bitcoin fell back below the $8,000 level for the first time in more than a week to halt its most recent rally, leading a wider retreat among cryptocurrencies.

The largest digital currency slumped almost 10% and was trading at $7,930 at 8:57 a.m. in Hong Kong, its biggest retreat in about two weeks, according to consolidated Bloomberg pricing. Bitcoin touched a year-to-date high of almost $9,100 on May 30, the data show. The wider Bloomberg Galaxy Crypto Index also fell as alternative coins including Ether and Litecoin retreated.

Bitcoin is down about 6% so far in June, after its best month since August 2017 amid a resurgence in investor sentiment following months of relative inactivity. Industry watchers pointed to renewed institutional interest this year with the likes of Facebook Inc. and JPMorgan Chase & Co. developing coins of their own.

“It just got a little bit extended, this is a healthy retracement,” said Timothy Tam, co-founder and chief executive at CoinFi, a cryptocurrency research firm in Hong Kong. “There’s quite a lot of volume going through, this is normal Bitcoin volatility. At the end of the day it still doesn’t take a lot of money to move these markets compared with traditional markets.”

Headwinds from the wider sell-off in global markets are also a factor, leading to “speculative flow” through alternative markets such as cryptocurrencies as well, Tam said.