The Z-Burger hamburger chain is facing criticism after it says a social media contractor posted an ad on Twitter depicting an American freelance journalist who was executed in the Middle East.

The incident unfolded over the weekend after a tweet for the Z-Burger chain showed a photo of James Foley, who was kidnapped in 2012 and beheaded by the Islamic State in 2014, with an image of a hamburger. According to Washingtonian, the ad read, “When you say you want a burger and someone says okay let’s hit McDonalds.” Under a picture of Foley was the message “You disgrace me.”

The Twitter ad has been taken down.

On Wednesday, Peter Tabibian, owner of the Z-Burger chain, repeated his apology for the incident and explained that he hired Valor Media of Raleigh, N.C., to run his company’s Twitter account. He said he didn’t approve of the posting beforehand, adding that he demanded the contractor take it down after he heard from an angry customer.

“I’m really sorry about what happened,” Tabibian said. “I take full responsibility for what happened. It is my company.”

He continued: “I trusted someone to do stuff on behalf of us,” he said. “I made a big mistake doing that. I’m very sorry to the Foley family and his friends and anybody who knows him.”

Valor Media didn’t immediately return calls and emails seeking a response, but issued an apology on Twitter.

In a tweet, Z-Burger said Valor had “caused unnecessary grief to the family, friends of journalist James Foley, and has been a callous misuse of images related to his untimely death in Iraq at the hands of terrorists.”

On Tuesday, Tabibian posted on Twitter that he was ending his relationship with Valor immediately.

In an interview Wednesday, Tabibian said he hired Valor about three months ago after checking references, giving them access to post to his business’ Instagram, Facebook and Twitter accounts to promote the chain.

He said when he saw the post on Foley, he “almost fell out of his chair and cried.” He said he’s tried to explain and apologize to many people, including those who knew Foley.

Tabibian is known among the local business community as a tenacious salesman. His family fled Iran in the early 1980s after receiving news that his father was expected to be arrested. He, along with his parents and sisters, left behind a profitable manufacturing business. After being smuggled into Turkey, he eventually landed in Switzerland, then Minnesota in 1984.

He came to the Washington area in 1988 and worked in several restaurants and ran a variety of businesses, including selling gumballs and neckties. He started Z-Burger in 2008. The chain has locations in Columbia Heights, Tenleytown, along P Street in Northwest Washington and in Towson, Md.

He said “anybody who knows me knows this incident is not me.”

Michael Valor, who runs Valor Media, took responsibility for the mistake.

At 23, Valor said he’s run his media company for five years. He said the incident happened after the company got an influx of work and that there had been a lack of oversight on a new art director. Valor said the art director involved with the tweet ad is a “really good girl” and the incident was “an act of ignorance not an act of maliciousness.”

Valor said “Z-Burger had nothing, nothing, absolutely nothing to do with this at all.” He also said, “I want to apologize for putting Z-Burger’s reputation on the line.”

In the Washingtonian article, Valor said the art director who used the image in the ad “didn’t know the image was of Foley.”

On Twitter, both Z-Burger and Valor promised to make donations to the James Foley Foundation.

Diane Foley, the mother of the slain journalist, wrote Tuesday in a tweet for the James Foley Foundation that she was “very saddened that @Zburger would be so insensitive and ignorant of others’ pain while marketing their hamburger.”

On social media, there were plenty of reactions to the Z-Burger mishap.

@kevinmetro13 wrote on Twitter, “they hired the contractors they are responsible.” One person on Twitter, @RobertNSockwell said Z-Burger “was blind-sided by the inappropriate tweet that was created and posted by the contractor, without Z Burger knowing.

Another Twitter post from @ForgetfulJeff said Valor’s video apologies came ” . . . off as insincere, and you should limit you[r] intake or your statements to written only.”

And @prettyrippedd said Z-Burger “should be boycotted for using image from James Foley’s death for a meme to sell burgers.”

Justin Moyer contributed to this report.