The sharp sell-off that gripped cryptocurrency markets on Wednesday has extended into a second day, with major digital assets across the spectrum continuing to fall during trading on Thursday.

Wednesday’s initial move seemed to have no real catalyst, beyond a theory put forward by Tanya Abrosimova of FXStreet is that the introduction of a registration process for the popular instant bitcoin exchange ShapeShift may have spooked some users and triggered at least part of the drop.

The slump was then exacerbated by a Business Insider report that Goldman Sachs has put plans to launch a bitcoin trading desk on hold for the foreseeable future.

That news saw bitcoin hold 4% lower at around $7,000 per coin, before falling again late on Wednesday evening. It has held relatively steady since then, but has now fallen more than $1,000 in value in just two trading sessions.

By around 9.40 a.m. ET, bitcoin is trading at $6,428, a drop of 4.1% since the session's beginning.

The crypto slump is impacting other currencies, with litecoin and bitcoin cash both lower by more than 3%, while ethereum, has slumped 20% in value over the past 24 hours, falling to its lowest level in over a year.

In line with ethereum's latest fall, hundreds of alt-coins on the website coinmarketcap.com have posted declines of around 20% over the last 24 hours.