BEIRUT (AP) — The health of a son of Libya's late leader Moammar Gadhafi was deteriorating three days into a hunger strike to protest his detention in Lebanon without trial, his lawyer said Tuesday.

Hannibal Gadhafi was suffering from headaches, muscle pain and difficulties moving around, his lawyer Paul Romanos said. He started his hunger strike Saturday.

He has been detained in Lebanon since 2015 after he was briefly kidnapped from neighboring Syria, where he had been living as a political refugee. He was abducted by Lebanese militants demanding information on the whereabouts of prominent Lebanese Shiite cleric Moussa al-Sadr who went missing in Libya 45 years ago.

Lebanese police later announced it had collected Hannibal from the northeastern city of Baalbek where he was being held. He has been detained in a Beirut jail without trial since then.

Romanos said Gadhafi was also suffering from back pain due to being held in a small room where he cannot move freely or exercise.

“He is continuing his hunger strike and his health is deteriorating,” Romanos told The Associated Press in a voice message.

A Lebanese security official who spoke on condition of anonymity said he had no information on Gadhafi’s health status.

The disappearance of al-Sadr in 1978 has been a long-standing sore point in Lebanon. The cleric’s family believes he may still be alive in a Libyan prison, though most Lebanese presume al-Sadr is dead. He would be 94 years old.

Al-Sadr was the founder of the Amal group, Arabic for “hope,” and an acronym for the militia’s Arabic name, the Lebanese Resistance Brigades. The group later fought in Lebanon’s 1975-90 civil war. Lebanon’s powerful Parliament Speaker Nabih Berri heads the group.

Most of al-Sadr’s followers are convinced that Moammar Gadhafi ordered al-Sadr killed in a dispute over Libyan payments to Lebanese militias. Libya has maintained that the cleric and his two traveling companions left Tripoli in 1978 on a flight to Rome and suggested he was a victim of a power struggle among Shiites.

Gadhafi was killed by opposition fighters in 2011, ending his four-decade rule of the north African country.

Hannibal Gadhafi was born two years before al-Sadr disappeared. He fled to Algeria along with his mother and several other relatives after his father's fall from power. He later ended up in Syria where he was given political asylum before being kidnapped and brought to Lebanon.