American electric car maker Tesla has unveiled its first electric articulated lorry, designed to challenge diesel trucks as king of the road.

The long-anticipated Tesla Semi has a range of 500 miles on a single charge, the BBC has reported.

Tesla says the vehicle - known in the US as a semi-trailer truck - will go into production in 2019.

Chief executive Elon Musk also unexpectedly revealed a new Roadster, which he said would be "the fastest production car ever" made.

The red sports car was driven out of the trailer of the electric lorry during Tesla's presentation yesterday.

The Roadster, which becomes available in 2020, will have a range of close to 1,000km (620 miles) on a single charge and will do 0-100mph in 4.2 seconds.

Mr Musk described it as "a hardcore smackdown to gasoline cars".

The Tesla Semi will achieve 0-60mph in 20 seconds when pulling 36,287kgs (80,000lbs), the maximum allowed on US roads.

Speaking on stage at Tesla's facility in Los Angeles, Mr Musk said: "It's not like any truck that you've ever driven."

With Tesla Semi, Mr Musk enters a competitive, demanding market, says the BBC. There are an estimated 3.5 million truck drivers in the US, the vast majority of whom drive diesel-powered engines.

Tesla will not be able to compete on diesel's range, and battery specialists doubt Tesla can produce a powerful enough battery at a reasonable price.

Picture credit: Pixabay