RELATED: All 12 boys and coach rescued from Thailand cave
Musk called Vern Unsworth a "pedo," or pedophile, in a tweet that has since been deleted.
Musk vented his anger after Unsworth said the mini submarine Musk sent to Thailand for the rescue was a publicity stunt. The sub was never used.
RELATED: Musk weighs in with cave rescue assistance
Unsworth's efforts in mapping the cave were credited with rescuing the 12 boys and their coach. But Musk questioned whether Unsworth was involved at all.
Unsworth says he's now considering suing because Musk called him a pedophile.