Trevor Milton, the founder and executive chairman of electric truck maker Nikola, has stepped down in the wake of allegations from a short-seller that the company misled investors and automakers.

In a statement released on September 20, Nikola Motor said Milton approached the board and proposed to voluntarily step aside. The company accepted his proposal and appointed Stephen Girsky as chairman, effective immediately. Girsky is a former vice chairman of General Motors and a member of Nikola’s board.

“Nikola is truly in my blood and always will be, and the focus should be on the Company and its world-changing mission, not me,” Trevor Milton said. “So I made the difficult decision to approach the Board and volunteer to step aside as Executive Chairman. Founding Nikola and growing it into a company that will change transportation for the better and help protect our world’s climate has been an incredible honor,” he added.

See Also: Justice Department And SEC Investigating Nikola Fraud Allegations

Nikola founder and former chairman Trevor Milton (left)

Milton said he’s confident Steve Girsky is the “right leader to guide our vision at the board level”, adding that the former GM exec has more than 30 years of experience working with OEM leaders, suppliers, dealers, labor leaders and national policy makers.

“On behalf of the board, I want to thank Trevor for his visionary leadership and significant contributions to Nikola since its founding,” said the new chairman, Steve Girsky. “Trevor saw the possibility of creating an end-to-end zero-emission transportation system when the industry was still in its nascent stages and took action to build the Nikola of today, with world-class partnerships, groundbreaking R&D, and a revolutionary business model. I know I speak for everyone at Nikola in our gratitude and in wishing him all the best.” Nikola’s executive team also includes CEO Mark Russell and CFO Kim Brady.

Earlier this month, short-seller Hindenburg Research alleged Nikola Motor misled investors and large automakers over its technology in a crushing report that sent Nikola’s shares lower. The EV startup denied claims it’s an “intricate fraud”, though it pretty much admitted faking a promotional video. Following the report, both the Securities and Exchange Commission (SEC) and the U.S. Justice Department began investigating Hindenburg Research’s claims.