A Palestinian doctor has died in an Israeli prison after more than four months in detention, Palestinian prisoner associations have said.

Dr Adnan Al-Bursh, 50, was the head of orthopaedics at al-Shifa Hospital.

The Israeli prison service confirmed that a statement published on 19 April about a prisoner who was detained for national security reasons and had died in Ofer prison was Dr Al-Bursh.

No details were given on the cause of death, and the prison service said the incident was being investigated.

But the Palestinian prisoner advocacy groups said in a joint statement on Thursday that Dr Al-Bursh's death was an "assassination" and his body still remained in Israeli custody.

Dr Al-Bursh was the head of orthopaedics at Gaza's largest medical facility, al-Shifa hospital, which has been raided several times by Israeli armed forces.

He was temporarily working at Al-Awada hospital in north Gaza when he was detained by Israeli forces.