After a period of low volatility, cryptocurrencies have broken out of their recent ranges, surging to multiweek highs on Thursday.

The No. 1 digital currency, bitcoin BTCUSD, -0.84% rose to a two-week peak, trading above $8,000 to an intraday high of $8,055.20, adding as much as 16%. A single coin last changed hands at $7,705.21, up 11%.

The intraday move is the largest since Feb. 6 when bitcoin traded down to $5,947.40 before closing at $7,700.39, a 29.4% move.

Wedge break out

The move comes after bitcoin spent the best part of two weeks in the $6,500 to $7,500 range. The tight sideways action created a so-called wedge formation, which can often presage significant swings in either direction once breached, according to market technicians

“We have seen consolidation in a very small range,” said Naeem Aslam, chief market analyst with ThinkMarkets

“When the consolidation is in such a tight range the probability is that a move to the upside can be two to three times the size of the consolidation range.”

BTC/USD

Aslam said that a move toward $10,000 by the end of the week would give full confirmation that a bull market is back in play, but a close below $8,000 would mean today’s move would just represent a short squeeze, where those investors betting on further declines in bitcoin would be forced to unwind those bearish positions. Such a squeeze can exacerbate a swing higher because so-called short sellers often need to purchase what they are betting against to unpack a short bet.

The ferocity of the move took bitcoin in to a so-called overbought territory, suggesting that it may pull back.

Read:Bitcoin may have already peaked, Barclays strategists say

Altcoins and futures follow bitcoins lead

The sudden surge in bitcoin also has propelled smaller coins, or altcoins, higher. Ether was last at $462.68, up 7.5%, Bitcoin cash is up 7% at $712.02, Litecoin has lagged, rising 3.6% to $123.38 and Ripple’s XRP is back above 50 cents, trading to 58 cents.

In the futures market, the Cboe’s April contract US:XBTJ8 closed Thursday up 11.2% at $7,695 and the CME Group Inc. April contract US:BTCJ8 finished the day at $7,680, up 11% on the day.

The value of all cryptocurrencies rose above $300 billion for the first time since March 28, according to research site CoinMarketCap.

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