Cairo, Jan 15 (AP) Egypt said Tuesday it would investigate the death in custody of a US citizen who had gone on a hunger strike as part of a six-year battle against what he insisted was wrongful imprisonment.

Mustafa Kassem, 54, an Egyptian-born auto parts dealer from Long Island, New York, died late Monday of heart failure after a hunger strike he began last year, his lawyers said.

The case has trained a spotlight on the dangers of Egyptian prisons, where many inmates are serving time for crimes they insist they did not commit, or have not been charged at all, as President Abdel Fattah el-Sissi escalates a crackdown on dissent.

Egypt's chief prosecutor ordered an autopsy and said officials are questioning all doctors who oversaw Kassem's care in prison and at the Cairo University hospital where he died.

In response to accusations of mistreatment and negligence, Egypt's interior ministry released a statement saying Kassem received proper medical care during his detention. The ministry said Kassem went on hunger strike despite warnings from prison authorities that his already poor health would deteriorate.

In Washington, Assistant Secretary of State for Near Eastern Affairs David Schenker told reporters that Kassem's death was "needless, tragic and avoidable." "I will continue to raise our serious concerns about human rights and Americans detained in Egypt at every opportunity," he said.

Kassem was in Cairo to visit family in August 2013 when his lawyers say he was mistakenly swept up in a vast dragnet during the violent dispersal of an Islamist sit-in that killed hundreds of people.

That summer, security forces descended on supporters of ousted President Mohammed Morsi, who hailed from the Muslim Brotherhood, in what became known as the "Rabaa Massacre."

Kassem was exchanging money at a shopping mall near Cairo's Rabaa al-Adawiya Square when police stopped him and asked to see identification. When he handed over his US passport, officers suddenly started beating him, and detained him. He was held for five years before he was charged.

Then in 2018, in a mass trial of over 700 defendants widely condemned by human rights organizations, Kassem was sentenced to 15 years under a contentious anti-protest law. After that, he refused to eat anything but vegetable juice, his lawyers said. Last week, he stopped even drinking.

When President Donald Trump secured the release of Egyptian-American rights advocate Aya Hijazi, who was imprisoned for three years in Egypt on false charges, Kassem appealed to the US administration for help. Vice President Mike Pence raised the issue last year with el-Sissi.

El-Sissi came to power the same summer of 2013 and has overseen a sweeping crackdown on dissent, silencing critics and jailing thousands. Rights groups accuse Egyptian prosecutors of detaining people without evidence, denying them access to lawyers and a fair chance to appeal.

"It's a scary precedent," Hijazi, who pressed for Kassem's release, told The Associated Press. "Both for what it means for the many political prisoners on hunger strike in Egypt right now ... but also for imprisoned US citizens that have called on American authorities to respond to no avail." Hijazi said Kassem was the fifth person to die in an Egyptian prison over the past month.

"He was targeted not because he was a criminal, but because he was American," she added, speaking about his arrest and imprisonment.

The death of Kassem, who suffered from diabetes, prompted accusations of medical negligence by activists, who say authorities restricted his access to much-needed medication during years of detention.

Kassem's case evoked that of Morsi, who was held in the same notorious Tora prison. The divisive but democratically-elected former president died last year while on trial in a Cairo courtroom, six years after his overthrow amid mass protests against his rule.

UN experts recently said that "brutal" prison conditions, including deprivation of vital diabetes medicine, contributed to Morsi's death. (AP)

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