• Khader Adnan has died in an Israeli jail after 86 days on a hunger strike
• Adnan's lawyer accused Israel of medical negligence
• Sirens rang out in Israeli-Gaza border communities

Khader Adnan, a commander of the Islamic Jihad who became a symbol of Palestinian resistance to Israeli detention policies, died on Tuesday after 87 days of hunger strike.

According to a statement from the Israeli Prison Service announcing his demise, Adnan, 45, had been on hunger strike since his arrest on February 5. During his detention, he also refused medical examinations.

Palestinian Khader Adnan Dies in Israel Prison

The prison service added that he was discovered deceased in his cell early Tuesday morning following his nearly three-month hunger strike. The Palestinian Prisoners Society also reported Adnan's demise, stating that "the Israeli occupation assassinated Sheikh Khader Adnan."

According to CNN, Adnan was arrested in February on suspicion of membership in a terrorist organization, support for terrorism, and incitement. He had never been tried prior to his death. The Palestinian militant group sponsored by Iran is responsible for the deaths of dozens of Israelis through suicide bombings and projectile attacks.

In mourning for Adnan, Palestinian political parties on Tuesday declared a general strike in the West Bank, closing schools, universities, and shops in response to the news of his demise.

Adnan "refused to undergo medical tests and receive medical treatment," according to Israel, and was "found unconscious in his cell" early Tuesday morning, local time.

Per ABC News, Israeli jail officials claimed Adnan was transferred to a hospital after attempts to revive him failed, and he was pronounced dead. According to the Israeli prison service, he was charged with "involvement in terrorist activities" this time.

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Jihad Warns Israel Would Pay for What Happened

Adnan's attorney accused Israel of medical negligence. "After 36 days of Adnan's arrest, we demanded he be moved into a civil hospital where he can be properly followed-up. Unfortunately, such a demand was met by intransigence and rejection by the Israeli prison authorities," lawyer Jamil Al-Khatib told Reuters.

Sirens sounded out in Israeli-Gaza border towns shortly after Adnan's death was revealed, sending people fleeing for safety. According to the Israeli military, three rockets were fired from Gaza into Israeli territory but landed in open regions.

Adnan's death is "a very dangerous thing that has happened," according to Mustafa Barghouti, former Palestinian communications minister and general secretary of the Palestinian National Initiative political organization.

Barghouti said the Israeli government and its national security minister, Itamar Ben-Gvir, "are personally responsible for this act of assassination."

Following Adnan's death, the armed group Islamic Jihad warned Israel that it would "pay the price for this crime," Aljazeera reported. According to the Palestinian Prisoners Association, Israel held Adnan 12 times, spending about eight years in jail, most of which was spent under administrative detention.

The Israeli human rights group HaMoked said Israel is keeping over 1,000 Palestinian inmates without charges or trial, the largest number since 2003.

The government claims that the contentious method helps officials foil assaults and detain dangerous radicals without revealing damning information for security reasons. Palestinians and rights groups believe the system is commonly misused and violates due process, with administrative prisoners and their attorneys unable to build a defense owing to the private nature of the information at issue.

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