Bitcoin hovers near $6 000 after 2018 low

Bitcoin traded above $6 000 on Monday morning after dropping below that level for the first time since February over the weekend, with the digital currency heading for a second straight quarterly decline.

The cryptocurrency was trading at $6 148.22 at 2:23 pm in Hong Kong, up 1.3% from its Friday close, according to composite Bloomberg pricing. It slumped to as low as $5 780 on Sunday, breaching the previous 2018 nadir set in February, according to Bitstamp prices.

Rival coins including Ripple, Ethereum and Litecoin continue to trade lower, the data show.

Bitcoin has tumbled more than 50% this year as regulators spanning the globe step up scrutiny of what some have criticised as a vehicle for fraud.

A series of hacks, including a $500m theft at a Japanese exchange in January and incidents in South Korea since then, have undermined confidence in the security of the digital currency.

• READ: Cryptocurrencies fall after Japan's regulator censures exchanges

In one of the latest flaps, private data including coin-wallet addresses and passwords for 19 clients were posted on a Kakao group chat on June 22, Kim Moon-hyung, an official with South Korean exchange Bitkoex, said by phone.

The official said there were no financial losses from the leak.

Sunday’s volatility came as the Bank of International Settlements, which serves as a clearing house and research and discussion forum for central banks, continued its critique of digital currencies.

The BIS’s head of research said many cryptocurrencies should be regulated like stocks and bonds.

On Friday, Japan’s Financial Services Agency ordered six of the country's biggest crypto-trading venues to improve measures to prevent money laundering. The companies must submit their plans by July 23.

New pressure in Japan, one of the most crypto-friendly jurisdictions, demonstrated the market's fragility to regulatory moves in the absence of much positive news.

The weekend slump took Bitcoin as low as $5 780 on Sunday, according to Bitstamp, one of the major price sources for cryptocurrencies, which have no unified quotation system. Bloomberg's composite pricing system includes Bistamp and several other sources.