Cryptocurrency exchange suspends all on-chain transactions of ETC after potential attack on the network. Attackers “double spend” about 219,500 ETC (nearly $1.1 million) worth of the digital currency. Attacker managed to recover previously spent coins from rightful recipients and transfer them to new entities chosen by attackers. Attack is not a one-time event, as the attacks are apparently ongoing, according to the firm. Bitcoin and other cryptocurrencies like Litecoin Cash, Bitcoin Gold, ZenCash (now Horizen), and Verge.
Source: https://thehackernews.com/2019/01/ethereum-double-spend-attack.html