Elon Musk's plans to sell 20,000 flamethrowers to the public have been described as "a slap in the face" by a Californian politician who wants to see the device banned.

Increasingly blurring fact with fiction, Musk is apparently producing 20,000 flamethrowers branded with the logo of The Boring Company, his firm which has received permits from the state of California to dig traffic-alleviating tunnels beneath Los Angeles.

But now Assemblymember Miguel Santiago is unimpressed with Musk's expansion from tunnel-digging to flamethrower-selling. Promoting the $500 device on Twitter and Instagram, Musk says he has already received 10,000 pre-orders, half of the planned 20,000-unit production run. The Boring Company is also selling a branded fire extinguisher for $30, which the firm itself describes as "overpriced".

Shipping will commence in the spring, according to Musk, but if his track record is anything to go buy then buyers could be waiting for much longer than that. Tesla is currently struggling to bring the production line of its new Model 3 electric car up to speed.

In a statement published on Twitter, Santiago said: "I honestly thought it was a joke when the article was read to me - while I was sitting in Los Angeles traffic. [We] have entrusted Mr. Musk to help alleviate a real public policy problem here by executing a tunnel under the city to help alleviate traffic. This deviation feels like a complete slap in the face."

Many believed it was a joke when Musk, who had already sold thousands of Boring Company-branded hats, said: "Hats sold out, flamethrowers soon!"

He then published a photo of the flamethrower to Instagram and suggested: "When the zombie apocalypse happens, you'll be glad you bought a flamethrower. Works against hordes of the undead or your money back!"

Pre-orders then opened, with Musk still seemingly in joke mode as he published the following tweets: "Obviously, a flamethrower is a super terrible idea. Definitely don't buy one...Unless you like fun….The rumor that I'm secretly creating a zombie apocalypse to generate demand for flamethrowers is completely false...But wait, there's more: the flamethrower is sentient, its safe word is 'cryptocurrency' and it comes with a free blockchain."

For a little extra weirdness, Santiago then referred to a Spider-Man quote in his statement. "Like most Americans, I am in awe of Mr. Musk's genius - the brains behind Tesla, PayPal, Solar City and SpaceX. But as President Truman and Stan Lee have taught us all, 'With great power comes great responsibility'...We don't allow people to walk in off the street and purchase military grade tanks or armour-piercing ammunition...I cannot even begin to imagine the problems a flamethrower would cause firefighters and police officers alike."

Some customers have expressed concern that buying the flamethrower could be illegal, but Musk says it is not classified as an illegal weapon by the Bureau of Alcohol, Tobacco, Firearms and Explosives because it produces a flame smaller than 10 feet. A video on Instagram suggests the flame is closer to two feet in length.

Is this an early and elaborate April Fools joke? Will the flamethrowers ever arrive in the mail? With Musk - a man who plans to launch his Tesla Roadster into Mars orbit next week playing David Bowie on loop forever - it is becoming increasingly difficult to tell.