Elon Musk has dragged pop star Taylor Swift in the ongoing controversy about his alleged Nazi salute at US President Donald Trump's inauguration.

Some across the political spectrum said the gesture looked like a "Heil Hitler" salute. The ADL said it was not.

Musk, 53, spoke to a crowd of Trump supporters at Capital One Arena in Washington, D.C., after Trump was sworn in at the U.S. Capitol. While thanking the supporters, Musk put his right hand over his heart, then extended his arm out with his palm down. He then turned around and repeated the gesture.