A former Palestinian prisoner, who developed muscular dystrophy while carrying out his sentence in Israeli jails, has died from the condition three years after he was released.

Rights groups say his death was the result of Israeli medical negligence in prison.

Naim Shawamreh, 46, died while hospitalised on Tuesday at the al-Ahli medical centre in the town of Dura, on the suburbs of the city of Hebron.

He was sentenced to life imprisonment in 1995 along with two other men for allegedly planting an explosive device and killing an Israeli explosives expert, charges that his family say are false.

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Shawamreh was released in 2013 after serving nearly 19 years in prison, following peace negotiations between Palestinian and Israeli leaders, in which 26 Palestinians who had served between 19 and 28 years in prison were freed.

"As he was being released, the authorities told him 'You are already dead," Shawamreh's brother, Nabil, told Al Jazeera, explaining that Shawamreh's health had severely deteriorated by the time he was released.

"We took him to Germany, to Jordan, and we even submitted our papers to go to the United States to get him further treatment, but nothing worked."

The reason why Shawamreh developed the disease in prison remains unclear.

'Medical Negligence'

Jerusalem-based prisoner rights group Addameer, whose lawyers regularly visited Shawamreh, says that because of the lack of healthcare, such cases in which prisoners die following their release from jail are common.

"Naim died as a result of the deliberate medical negligence in Israeli prisons. He would not have got to this point if he had been taken care of," Muhammad el-Azza, a lawyer at Addameer, told Al Jazeera.

"In general, there is an attitude in Israeli jails of disregard for all prisoners, and on all levels - whether from an Israeli dentist or physicians that deal with chronic diseases. They are deliberately slow in giving the prisoners treatment. Often it takes the prison services months or even years to get a patient to surgery."

Azza added that prisoners are treated very poorly at Ramle hospital, run by the Israeli Prison Service, in which Shawamreh was being held.

"They are chained from their arms and legs on the beds. The room remains shut all the time, and those who need assistance - such as someone to help them get up or move around - are ignored."

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According to the Hebron-based Palestinian Prisoner's Study Centre, there are about 280 Palestinian prisoners who have died in prison, or shortly after their release.

"Today, the case of Naim Shawamreh sheds light on the cases of hundreds of other sick prisoners in Israeli jails," said Osama Shaheen, the centre's director.

There are 1,200 prisoners that are currently sick inside the prisons. Twenty-one of those are in very critical condition and are being treated at Ramle hospital, according to Shaheen.

"We ask the world to pay attention to our prisoners as they get sicker and sicker in Israeli jails, and we pray that all our prisoners are released," Nabil told Al Jazeera.

"They are suffering."