An 11-year-old boy in the United Kingdom collapsed and died last month after eating a chocolate bar because of a severe allergy, according to a coroner's report released Monday.

Raffi Pownall, who had a severe dairy allergy, was accidentally given a chocolate bar containing milk powder as a treat by his father, Tom, on June 8.

Tom Pownall told officials that he thought the chocolate was dairy-free, according to the Manchester Evening News, as he bought it from British grocery store Morrisons in a section for people with dietary restrictions.

It turns out the chocolate he purchased was actually gluten-free, not dairy-free.

Raffi immediately became "distressed" from a sliver of the chocolate, and using an EpiPen and his inhaler did not work immediately.

After being transported to the hospital, Raffi died of anaphylaxis relating to his ingestion of the chocolate, multiple allergies and severe asthma, according to a coroner's office report published Monday and obtained by USA TODAY.

''I genuinely believed this bar was a free-from-dairy chocolate bar," Pownall said to officials, the Manchester Evening News reported. "This has been tragic. It was ingested entirely by accident."

Neither the Pownall family nor Morrisons immediately responded to a request for comment by USA TODAY.

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