San Francisco, Dec 6 (IANS): After his call to either be "extremely hardcore" at work or quit, Elon Musk has converted rooms at Twitter headquarters in San Francisco into small bedrooms, featuring unmade mattresses, drab curtains and giant work monitors, the media reported.

The beds are prepared for remaining "hardcore" staffers to be able to stay overnight at the office, reports Forbes.

As employees came to the office on Monday, they saw several rooms in the office being converted into "small sleeping quarters", the report mentioned, citing sources.

The bedrooms have "bright orange carpeting, a wooden bedside table and what appears to be a queen bed, replete with a table lamp and two office armchairs just begging for convivial workplace collaboration".

There was no announcement from Musk or the company about the move, leaving employees surprised as well as shocked.

"It's not a good look. It's yet another unspoken sign of disrespect. There is no discussion. Just like, beds showed up," a source was quoted as saying in the report.

Sources told Forbes that there were maybe "four to eight such rooms per floor" at the Twitter HQ.

Last month, Musk game employees ultimatum that they have to perform "extremely hardcore" work or leave the micro-blogging platform.

"Going forward, to build a breakthrough Twitter 2.0 and succeed in an increasingly competitive world, we will need to be extremely hardcore," Musk wrote in an internal memo too employees.

"This will mean working long hours at high intensity. Only exceptional performance will constitute a passing grade," he said.

There were reports of Twitter employees sleeping on the floor at the office after Musk took over the company.

Musk had earlier said that he's worked as much as 120 hours a week at times and slept on the floor at a Tesla factory.