Bitcoin headed for another weekly slump on Friday, with the largest cryptocurrency heading closer to US$3 000 — a level unseen since September last year.

The largest digital currency edged 0.5% higher to $3 272 at 9.35am in Hong Kong after earlier tumbling as much as 6% in US hours, according to consolidated pricing compiled by Bloomberg. It remains down about 3% for the week. The wider Bloomberg Galaxy Crypto Index is on a five-week losing streak.

Cryptocurrencies have wiped out $730-billion in market value from a January peak this year, according to data compiled by CoinMarketCap.com. Widespread mainstream institutional adoption failed to materialise amid ongoing security concerns and regulatory roadblocks.

A wave of bomb threats demanding bitcoin spread across the US and Canada on Thursday, including New York, Toronto and other major cities. Security researcher KrebsonSecurity posted a copy of the e-mail on its website — the apparent scammers requested payment of $20 000 in bitcoin. New York City’s police department said the threats were not deemed credible. — Reported by Eric Lam, (c) 2018 Bloomberg LP