The exact cause of his death on Wednesday has not been made public but police said they did not believe it was a criminal act.
“Twenty-four years. That's nothing, this is a catastrophe,” Simon Pasternak, head of publisher Gyldendal, said in an Instagram post. “I have known him, since he was 16 years, this brilliant boy with enormous talent.”
Police in Aarhus, the country's second largest city where Hassan lived, told local media that they had responded to reports of the death of a man in his mid-20s.
“Currently there is nothing in our investigation that indicates that this is a criminal act,” police spokesman Jakob Christiansen told newspaper BT.
Hassan's debut poetry collection was printed in a record 120,000 copies after it was released in 2013, in a country where poetry collections are usually printed in the hundreds.
Writing in all capital letters without any punctuation, he used street slang and blunt word play to deliver a damning indictment of his parents' generation of immigrants who came to Denmark in the 1980s, describing domestic violence, benefit fraud and religious hypocrisy on the Aarhus housing estate where he grew up.
In the poem “Satellite dish” he wrote: “WE HAD NO DANISH CHANNELS/WE HAD AL JAZEERA … WE HAD NO PLANS/BECAUSE ALLAH HAD PLANS FOR US.”
“Yahya insisted on not bending to anyone, he didn't want to be anyone's representative… He wanted to be himself,” Pasternak said.
Many young Danes of immigrant origin disliked Hassan for his negative views on their communities and their religion. In November 2013, he was assaulted in Copenhagen's main train station by a 24-year-old man previously convicted of trying to commit an act of terror.
In November 2019, Hassan released a follow up poetry collection, which like the first was named after himself, also to critical acclaim.
In between, he made headlines more for his rantings, his attempts to enter politics and his dealings with justice than for the quality of his writing.
In 2016, he was sentenced to one year and nine months in prison for shooting a 17-year-old boy with a pistol, wounding the boy's foot and leg.