Plans for an electric transport vehicle have been anticipated since Musk revealed the second part of his “master plan” for the Palo Alto-based automaker in July last year.
Musk wrote in his blog then that the company would step beyond the car market and begin work on self-driving semis, pickup trucks and buses.
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In a tweet on Thursday, Musk commended the project team for doing an "amazing job" and promised that the semi would be "seriously next level."
The commercial truck will be followed by a pickup truck for the consumer market in "18-24 months," Musk subsequently tweeted.