Facebook has been accused of age discrimination after they allowed employers like Amazon and Verizon to exclude millions of older Americans from seeing their job ads.

A joint investigation by the New York Times and ProPublica revealed that the telecoms giant recently posted a recruitment ad for jobs in financial planning and analysis - but restricted the post to Facebook feeds for users aged between 25 to 36, who lived in Washington DC and demonstrated an interest in finance.

That meant that an older yet more experienced financier living in the capital, even one looking for jobs in their field, would never see the ad.

Facebook Careers also posted an ad for jobs in their own engineering department, although only people aged 21 to 55 who live in the United States could see it.

Facebook has been accused of age discrimination after they allowed employers like Amazon and Verizon to exclude millions of older Americans from seeing their job ads. Pictured is the Verizon ad

'It's blatantly unlawful,' said Debra Katz, a Washington employment lawyer who represents victims of discrimination, citing the federal Age Discrimination in Employment Act of 1967, which prohibits bias against people 40 or older when hiring.

But Facebook has defended the age exclusive ads, saying that they were a common industry practice.

'We completely reject the allegation that these advertisements are discriminatory,' said Rob Goldman, a Facebook vice president.

'Used responsibly, age-based targeting for employment purposes is an accepted industry practice and for good reason: it helps employers recruit and people of all ages find work.'

Verizon did not respond to reporters' requests for comment.

Mark Zuckerberg has previously pledged to improve transparency at Facebook

UPS also targeted an ad for part time package handlers at people 18 to 24 who live in or visited Allentown, Pennsylvania.

Other employers, including Amazon, Northwestern Mutual and the New York City Department of Education, all say they are changing their recruiting policies.

An Amazon spokesman told The Times that they have reviewed the way their ads were delivered on Facebook and found they were 'inconsistent with our approach of searching for any candidate over the age of 18.'

'We have corrected those ads.'

Other companies argue that age targeted ads on Facebook are no different than posting an ad in a magazine like Teen Vogue which aims contents at teens.

But others say that anyone is able to buy such magazines and read the job ad, while an older person on Facebook would never even know about the ad.

'Once you reach your 50s, you may as well be dead,' said Mark Edelstein, a social-media marketing strategist who is 58 and legally blind. 'I've gone into interviews, with my head of gray hair and my receding hairline, and they know I'm dead.'

Edelstein, who is currently looking for work, said that he's been looking for jobs on sites like LinkedIn and Indeed, but says he never sees adverts for jobs in his profession on Facebook.

Meanwhile, HubSpot had posted a job for social media director on Facebook, but limited it to people aged 27 to 40, in the United States.

'Hypothetically, had I seen a job for a social media director at HubSpot, even if it involved relocation, I ABSOLUTELY would have applied for it,' Edelstein said.

'It doesn't surprise me a bit. Why would they want a 58-year-old white guy who's disabled?' he added.

A HubSpot spokeswoman defended the job posting saying it also appeared on LinkedIn and other recruitment sites, and said it was open to anyone regardless of age.

Facebook is not a recruitment specialist but it is increasingly being used by recruiters as a way to promote their jobs, over traditional job hunting sites such as Linkedin, because the social network has such a bigger market; two billion monthly active users compared to LinkedIn's 530 million total members.

But it's not the first time that Facebook's targeted ads have come under fire.

The tech giant acknowledged it had found more than 3,000 ads linked to Russia that focused on divisive U.S. social issues and were seen by an estimated 10 million people before and after the 2016 elections.

They told Congress that ads representing 'foreign interference' in America's election system continued after Donald Trump won the White House.

Much of the focus on Russian involvement has come as part of a larger story that suggests Moscow instead sought to help Trump win the White House over Hillary Clinton.

But Facebook General Counsel Colin Stretch said in a Senate Judiciary Committee hearing that while his company first spotted the ads in the presidential primary season two years ago, they continued to run 'following the election.'

'We saw this concerted effort to sow division and discord,' Stretch explained. 'In the wake of the election – and now-President Trump's election – we saw a lot of activity targeted at fomenting discord about the validity of his election.'

The ads 'continued until we disabled the accounts,' he said.

Testimony from Facebook reveals that posts generated by a Russian outfit may have reached as many as 126 million users. Pages created by Russia's Internet Research Agency generated 80,000 posts on 120 pages between January 2015 and August 2017.

Possible views reached into the millions after people 'liked' the posts and shared them.

Stretch told the committee that 'we take what happened on Facebook very seriously; the foreign interference we saw is reprehensible.'

'That foreign actors hiding behind fake accounts abused our platform and other Internet services to try to sow division and discord – and to try to undermine our election process – is an assault on democracy, and it violates all of our values,' Stretch said.

Facebook's Goldman said the company is striving for more transparency, and plans to build a new archive of federal election ads on Facebook, including the total amount spent and the number of times an ad is displayed.

The archive, which will be public for anyone to search, would also have data on the audience that saw the ads, including gender and location information. The archive would eventually hold up to four years of data.

Goldman said the company is still building the new features. They plan to test them in Canada and roll them out in the United States by next summer ahead of the 2018 midterm elections.

'This is a good first step but it's not at all the last step, there's a lot to learn once we start testing,' Goldman said in an interview.

Facebook already had announced in September that the platform would require an advertiser to disclose who paid for the ads and what other ads it was running at the same time. But it was unclear exactly how the company would do that.

The moves are meant to bring Facebook more in line with what is now required of print and broadcast advertisers. Federal regulations require television and radio stations to make publicly available the details of political ads they air. That includes who runs the ad, when it runs and how much it costs.