https://www.bleepingcomputer.com/news/security/hacker-makes-over-18-million-in-double-spend-attack-on-bitcoin-gold-network/

An unidentified hacker has mounted several "double spend" attacks on the infrastructure of the Bitcoin Gold cryptocurrency and has managed to amass over $18 million worth of BTG (Bitcoin Gold) coins in the process.

According to a post on the Bitcoin Gold forums, the attacks have started taking place since last Friday, May 18.