Tesla shares edged higher in early Friday trading, but have lost nearly have of their value since mid-December, and a top Wall Street analyst suggests there could be more declines ahead tied to weakness in the group's core automaking business.

Tesla backlash continues as the stock nosedives and Musk pushes conspiracy theories about protests and arsons at dealerships.

The speaker of the House of Representatives (R-Louisiana) said Congress would probe “domestic terrorism” attacks on the Tesla brand after the company's vehicles, dealerships and charging stations were targets of vandalism,