In the battle for America’s hearts and minds on social media, Amazon has apparently enlisted some of its warehouse workers.

A group of more than a dozen Amazon Twitter users in the last two weeks started responding to critics of the company on the social media site, sharing upbeat tales of their working conditions and pay at Amazon’s distribution network.

Identified by first names and “Amazon FC Ambassador,” they each opened a Twitter account this month, are unfailingly polite, and pepper emojis into conversations about the generosity of their benefits packages and job satisfaction at Amazon’s fulfillment centers, the company’s term for its sprawling warehouses.

In a typical interaction, one non-Amazon Twitter user opined that “the way Amazon treats its workers is shameful,” and linked to a news article about retailers that compete with Amazon.

Cindi, an Amazon “ambassador” from Etna, Ohio, replied with information about her work breaks.

“The way Amazon treats its employees is GREAT, we work hard, have fun and are always ready to make history,” she posted. “We have several break rooms throughout the facilities, I get two 30 mins breaks through my shift which is great.”

Amazon’s Twitter legion, though small, appears to represent a new front in the company’s effort to portray itself as a generous employer. The company has been criticized for years by activists and labor unions for working conditions in its warehouses, with media reports finding the company failed to provide air conditioning at some facilities during the summer, and set work quotas that could exceed employees’ ability to keep up. (Recently, an author alleged that employees at a British warehouse were afraid of taking a trip to the bathroom for fear of missing productivity targets.)

The Seattle company in recent years has expanded its program of public warehouse tours, as well as Career Choice, its initiative that offers to help warehouse workers find their way into other careers like nursing or commercial truck driving.

In a statement to the Guardian newspaper, later confirmed by the company, spokesman Ty Rogers said the Twitter users were real employees in Amazon warehouses, but didn’t comment on the origin of the effort.

“FC ambassadors are employees who understand what it’s actually like to work in our FCs,” Rogers said. “The most important thing is that they’ve been here long enough to honestly share the facts based on personal experience. It’s important that we do a good job of educating people about the actual environment inside our fulfillment centers, and the FC ambassador program is a big part of that, along with the FC tours we provide.”

Many Twitter users were skeptical of the effort, writing to the employees to accuse them of taking part in a PR campaign.

Not so, the employees said.

“There doesn’t have to be an angle to love what we do and share it with the public,” said Ambassador Sean.

Natalie Mizik, a professor at the University of Washington Foster School of Business who studies marketing, said she wasn’t aware of any other companies asking rank-and-file employees to post testimonials on social media. “I’m surprised that this is so well-organized, for employees not in the public-relations department.”