Ethereum Classic (ETC) has denied it has experienced a 51% attack and the presence of a double spend, as alleged by Coinbase.

On January 5, Coinbase claims to have detected a “deep chain reorganization” of Ethereum Classic, including evidence of double spend. In response to the suspicious activities, Coinbase has since suspended all movement of affected funds on the ETC blockchain to protect its customers.

ETC refuted the claim, saying “ETC network is operating normally”. It has blamed a mining pool for some of the suspicious behavior by engaging in “selfish mining.”

Although Coinbase pointed out the ETC reorganizations could result in a double spend amounting to a value of $450,000, it claims it is “not the target of this double spend and no funds were lost.”

Coinbase is not the only exchange suspending all ETC activities. ETC wallets on Poloniex, Liquid, and Kraken have been temporarily suspended due to the alleged attack on the ETC blockchain. Coinbase has not resumed ETC withdrawals and deposits while it is still monitoring ETC activity.