Twitter owner Elon Musk apologized on Tuesday after facing a wave of criticism from social media users over a viral public exchange with an employee who was unsure if he'd been fired.

The now former employee, Haraldur Thorleifsson, appealed to Musk for clarity on his employment status. What resulted, however, was an exchange where Musk claimed Thorleifsson "did no work" and sought to cast doubt on his disability.

What happened?

Haraldur Thorleifsson, who uses a wheelchair and goes by the name "Halli" on Twitter, first noticed on at the end of February that he could not log on to the company's systems.

When he asked the company's HR department whether he'd been let go, Thorleifsson said he did not receive a clear answer.

After nine days of being locked out of the system, he turned to Twitter for answers and tagged Musk.

"Maybe if enough people retweet you'll answer me here?" he wrote.

Musk replied, but began quizzing Thorleifsson on the tasks he performed at Twitter and what his role was.

As the exchange went on, and the discussion around it grew, Musk claimed that Thorleifsson "did no actual work."

He continued, saying the laid off employee "claimed as his excuse that he had a disability that prevented him from typing," but criticized the man for "tweeting up a storm."

"Can't say I have a lot of respect for that," Musk wrote.

'Would have been nice' to know about layoff, says ex-employee

Thorleifsson, who has muscular dystrophy and uses a wheelchair, said the information Musk publicly tweeted was "confidential health information."

"For a long time I thought my arms would remain strong. A doctor told me they would. But they ended up losing strength. Which, I don’t mind telling you, was hard to accept," he wrote.

"The reason I asked you in public is because you (or anyone else at Twitter) didn't reply to my private messages."

"You had every right to lay me off. But it would have been nice to let me know!" he added.

Thorleifsson, who lives in Iceland, joined Twitter in 2021 when the company acquired his startup Ueno.

He opted to be paid in wages for the purchase price of his company in order to pay taxes into Iceland's social services — a move that garnered praise in Icelandic media.

How has Musk responded to the criticism?

Musk's comments drew ire from users on the platform, many of whom questioned whether Musk's remarks about Thorleifsson's disability were legal.

On Tuesday evening, Musk apologized for his response.

"I would like to apologize to Halli for my misunderstanding of his situation. It was based on things I was told that were untrue or, in some cases, true, but not meaningful," he wrote.

Musk said he'd spoken with Thorleifsson in a video call several hours after the exchange.

Business magnate Musk has been embroiled in a string of controversies since acquiring Twitter in October 2022. Shortly after his leveraged $44 billion takeover, he initiated several rounds of layoffs that saw over two thirds of the company's staff let go.

Musk has also ignited a backlash over planned changes to Twitter, such as introducing a charge for the blue tick which indicates active, notable, and authentic accounts of public interest.

Musk has also raised eyebrows in the past over his inflammatory posts on the platform.