Lewis Hamilton has raised fears among the Formula One fraternity after posting a cryptic social media message in which he says he is ready to “give up" on the world.
The British superstar, who is on the brink of clinching his sixth F1 world title, missed out on victory at the Japanese Grand Prix last weekend.
It is unclear what Hamilton's worrying post is referring to, although the 34-year-old has recently been vocal on Instagram over his attempts to avoid damaging the planet.
Hamilton, who turned vegan in his bid to improve his lifestyle, wrote on Instagram: "Honestly, I feel like giving up on everything. Shut down completely. Why bother when the world is such a mess and people don't seem to care.
"I'm going to take a moment away to gather my thoughts. Thank you to those of you who do give a damn about the world."
Hamilton immediately received support from his fans with one posting: "I hope you're okay Lewis. I just saw your Insta story. We're all here for you. Love you."
The Mercedes driver recently urged his fans to boycott shows featuring marine animals and called on them to educate themselves about the "horrible" things that happen to animals in captivity.
He wrote: "So I'm back in Japan, one of my favourite places in the world. One of the most beautiful, peaceful wonderful places," he wrote.
"The culture, the people, the food and cities are wow. But do you know, this happens here in Japan. Please please don't go and support these shows around the world, don't buy tickets to show your kids.
"Instead, educate them of these horrible things that have happened to the dolphins, whales, and other sea life. These beautiful creatures shouldn't suffer."
The five-time world champion also previously revealed his concerns about the meat industry, and its potential effects on the environment, animal welfare and human health.
He told the BBC in 2017: "I stopped eating red meat two years ago. I have generally been pescatarian for the majority of the year and now I've cut fish.
"As the human race, what we are doing to the world... the pollution [in terms of emissions of global-warming gases] coming from the amount of cows that are being produced is incredible.
"They say it is more than what we produce with our flights and our cars, which is kind of crazy to think. The cruelty is horrible and I don't necessarily want to support that and I want to live a healthier life."
Hamilton, meanwhile, will win his sixth championship a week on Sunday in Mexico City if he takes the chequered flag and team-mate Bottas finishes fifth or lower.
But the Mercedes cars have struggled at the high-altitude venue in recent seasons, and Hamilton fears he will have to wait for a title, which will move him to within one of Michael Schumacher's record.
The US Grand Prix follows the round in Mexico before the season's final races in Brazil and Abu Dhabi.
Hamilton, 34, added: "For me it has never been a case of wanting to rush things. Valtteri has driven well all year long, and done well, and he will most likely do a very solid job over the next few races.
"So we still have a battle and the fight continues. Mexico is our Achilles heel, our worst race of the year, so it is going to be a tough one for us. The last few have been pretty shocking.
"It going to be very hard to beat Ferrari there. I don't anticipate it will be Mexico where I win it the title."
