Stock markets retreated Monday after a sustained rise to successive records last week, against a backdrop of fast-rising coronavirus cases and U.S. political turmoil.

And cryptocurrency bitcoin plunged, posting its biggest loss since the start of the pandemic.

Though investors were unmoved by the violent invasion of the U.S. Capitol by President Donald Trump's supporters last week, they were shaken by the aftermath amid Democratic efforts to remove him from office.

All three major U.S. indices pulled back, and tech shares also felt the fallout after social media platforms pulled the plug on Trump.

"Investors are hitting the pause button with the relentless buying of U.S. stocks as big-tech's actions following the mayhem at the Capitol drags sentiment down," said Edward Moya at the online brokerage Oanda.

Art Hogan, chief market strategist at National Securities, said investors can only ignore bad news for so long.

The bad news included data showing spiking COVID-19 cases led in December to the first job losses since April.

The market "was able to look through the insurrection, the attack on the Capitol (and) lousy job numbers last week," he told AFP.

"But you get to a point where you have to stop pricing in the future and look at the here and now."

Analysts cite concerns the repercussions could be felt for months if efforts to again impeach Trump undermine President-elect Joe Biden's efforts to push through his economic stimulus plan, which he said he will unveil this week.