Bitcoin investment products and funds posted their sixth consecutive week of outflows, according to data on Monday from digital asset manager CoinShares as a crackdown in China spooked investors.

Last week, bitcoin outflows totaled $89 million. For the year, bitcoin outflows hit $487 million, or 1.6% of assets under management, data showed.

The crypto sector as a whole saw a third consecutive week of outflows amounting to $79 million last week in what is now the longest bear run in outflows since February 2018, CoinShares said. For the month of June, net outflows hit $210.5 million.

"Bitcoin's six-week run of outflows has been driven by the combination of environmental concerns and an increasingly antagonistic regulatory environment in China," said Matt Weller, global head of market research at Forex.com

"With these themes still in effect and prices subdued, it may be a while before we start to see another period of sustained fund inflows," he added.

Bitcoin on Monday hit a two-week low of $31,700, undermined by China's expanding crackdown on bitcoin mining. Authorities in the southwest province of Sichuan ordered cryptocurrency mining projects closed in the major mining center.

Bitcoin has lost over 20% in the last six days and is down by half from its April peak of almost $65,000.

Ether, the token used for the Ethereum blockchain, saw minor outflows of $1.9 million last week, after posting outflows of $14.6 million the previous week. As a percentage of assets under management, the ether outflows represented just 0.14%, data showed, implying that most of the negative sentiment has been focused on bitcoin.

Weekly trading volumes in ether investment products have fallen dramatically, down 80% since the May highs.

Blockchain data provider Glassnode said on-chain activity across the board is remarkably low across bitcoin and ethereum.