Ghazi Ezzeldin, a 54-year-old Lebanese man who worked in construction in the UAE, died on 4 May after being detained for about two months by Emirati authorities.
He was arrested on 22 March, alongside two of his brothers and seven other Lebanese from the town of Barish in southern Lebanon.
His death has caused outrage in his home town, as allegations that he was tortured to death by Emirati authorities circulate.
A source close to Ezzeldin's family told The New Arab that Ezzeldin's son was summoned late at night and brought to a cemetery, where he was asked to identify his father's body.
Security officials would not allow the son to inspect the whole body, but would only let him see his father's face.
Officials also denied the request of the son to repatriate his father's remains to Lebanon, telling him that they had already prepared the body for burial according to proper Shia custom.
They then buried the body in front of the son and the two brothers of Ezzeldin.
The brothers were subsequently released from prison but have not been allowed to leave the country, despite being discharged without any charges raised against them.
"The burial took seconds, and they wouldn't let [the son] see the body. Of course, this means it was torture," the source said.
Euro-Med Monitor said that it "obtained a statement" which pointed to torture as a possible cause of Ezzeldin's death, but said that it was not able to independently verify the claim.
"There is absolutely a need for transparency from the UAE on this case. If they have nothing to hide, they should allow the family to take the remains back to Lebanon," Sima Watling, the UAE researcher at Amnesty International, told TNA.
"If it's proven that torture is involved, then they must conduct an impartial and independent investigation and those responsible must be punished," Watling said.
Mass arrests of Lebanese in the UAE are relatively common, particularly against Shia Muslims or those living in areas associated with the pro-Iran group Hezbollah.
Watling added that many of these mass arrests and subsequent trials "don't follow the basic standards for fair trials."
According to Abu al-Fadl al-Chouman, the founder of the "Committee of Emirati Detainees" which advocates for Lebanese imprisoned in the UAE, all of the Lebanese who were released from UAE prisons described undergoing torture.
"Those that were released, all of them told us they were subjected to the most heinous form of torture," al-Chouman told TNA.
He expressed concern that the remaining seven Lebanese arrested alongside Ezzeldin were currently undergoing abuse in Emirati prisons and urged their release.
The source close to Ezzeldin said that family members had lobbied the Lebanese government through a variety of avenues to try to secure Ezzeldin's release but to no avail.
"All of Ramadan they told us, 'next week, next week.' But nothing happened," they said.
Mohammed Moghabet, the Lebanon director at Euro-Med Monitor, said that the Lebanese government has a "responsibility" to take all possible measures to defend its citizens in foreign countries.
"The UAE on the other hand must cooperate with the Lebanese authorities to make sure that the perpetrators are prosecuted," Moghabet told TNA.
TNA reached out to an Emirati press spokesperson for a comment on this story but had not received a reply by the time of publishing.