Romain Grosjean is being treated for burns to his hands and will stay in hospital overnight after miraculously walking away from a huge first-lap crash at the Bahrain GP that saw his Haas car split in two and burst into flames.

The Frenchman, who has not suffered any fractures, crashed heavily when swerving to the right of the straight after just two corners of Sunday's race, with his Haas car piercing the barrier at high-speed with a huge and frightening impact to red flag the Grand Prix.

Speaking for the first time from his hospital bed in a video posted on Sunday night, Grosjean said he was "okay... sort of okay".

Grosjean incredibly, emerged from his cockpit before being rescued by nearby marshals and medical officials - while flames engulfed the front half of his car.

Sustaining only minor suspected injuries, Grosjean was taken to Bahrain's Defence Force Hospital for further checks and the FIA said in a statement on Sunday night that he was being "treated for burns sustained on the back of both hands" and would remain in hospital overnight.

X-rays also showed he had sustained no fractures.

The FIA is launching an investigation into what happened in the accident.

"We will look at it all and undertake a full investigation of the whole incident, and what we can learn," said race director Michael Masi to Sky Sports F1.

Grosjean speaks from hospital bed: Halo saved my life

Appearing in good spirits as he posted an Instagram video from his hospital bed, the Frenchman thanked medical teams at both the circuit and the hospital - and credited the Halo head protection device, introduced to F1 in 2018, for allowing him to walk away from the accident.

"Hello everyone, just wanted to say I am okay... sort of okay," he said, as he waved hands heavily wrapped in bandages.

"Thank you very much for all the messages."

"I wasn't for the Halo some years ago but I think it's the greatest thing we brought for Formula 1, and without it I wouldn't be able to speak to you today.

"Thanks to all the medical staff at the circuit and at the hospital and hopefully I can write to you quite soon some messages and tell you how it's going."

Haas boss Guenther Steiner earlier told Sky F1: "I just spoke with him on the phone, he's in a clear state of mind, he is good.

"They are still staying at hospital overnight, they want to keep him there, but he told me that he feels good, nothing is broken. He's got his hand bandaged from the burns, he was very happy."