Baseball superstar Jose Fernandez killed in boat accident at age of 24

He was just 24 years old.

Full details of the accident have yet to emerge, but two other people also lost their lives in the accident off Miami Beach in the early hours of Sunday morning.

Lorenzo Veloz of the Florida Fish and Wildlife Conservation Commission, the organisation responsible for the crash investigation, said that the 32ft boat had suffered a "severe impact" with a rocky jetty.

"t does appear that speed was involved due to the impact and the severity of it," said Veloz.

"It does appear to be that they were coming at full speed when they encountered the jetty, and the accident happened."

Adding to the heartbreak is the fact that Fernandez's girlfriend is pregnant, news that he shared with the world via social media just five days ago.

His team, the Miami Marlins, released a statement saying that they were "devastated" by the loss, and cancelling their game on Sunday evening against Atlanta.

Tributes quickly poured in for one of the most popular players in the game, a $3 million-a-year pitcher with a knack of hitting home runs.

"He was one of our game's great young stars who made a dramatic impact on and off the field since his debut in 2013," said MLB Commissioner Rob Manfred.

"Our thoughts and prayers are with his family, the Miami Marlins organization and all of the people he touched in his life."

Those skills saw him named MLB rookie of the year in 2013, and won him a spot on the All-Star teams in both 2013 and 2016.

One of the tributes came from a reporter reminding the world that Fernandez had saved his mother's life as he escaped from Cuba to make it to the USA while still a teenager in 2007.