Hilarion Capucci
Hilarion Capucci of the Melkite Greek Catholic Church takes part in a rally in support of Syrian President Bashar Assad, in downtown Rome, Aug. 30, 2013. REUTERS/Max Rossi

Archbishop Hilarion Capucci, who was convicted of smuggling arms for Palestinian militants died Sunday in Rome aged 94. The Vatican confirmed his death Monday, but the cause of his death remains unclear.

Capucci was the head of the Greek Catholic Church in Jerusalem. He was arrested in 1974 and charged with using his Mercedes sedan to smuggle arms to Palestinian militants, following which he served two years of a 12-year sentence in Israel. He was later freed in 1977 following a personal appeal by Pope Paul VI.

Mahmoud Abbas, president of the Palestinian National Authority, praised Capucci for “defending the rights of the Palestinian people.”

Capucci was born on March 2, 1922, in Aleppo, Syria, which was then under French control. He was ordained a priest of the Basilian Alepian Order of the Melkite Greek Catholic Church in 1947 and was appointed Patriarchal Vicar of Jerusalem and Archbishop of Caesarea in 1965.

Capucci remained in the headlines following his release in Israel, attempting to mediate in the Iran hostage crisis. He visited Americans held captive at the U.S. Embassy in Iran in 1979, and also accompanied the bodies of eight U.S. service members who were killed in an unsuccessful mission to free the hostages. He later traveled to Saddam Hussein's Iraq in 1990 to help secure freedom for 68 Italians prevented from leaving following the invasion of Kuwait.

Capucci reportedly boarded the Mavi Marmara, the Turkish-owned ship bound for Gaza that was seized by Israeli forces when it attempted to violate Israel’s naval blockade.

In a 2010 interview with Al Jazeera, he reportedly said he had taken part in the Gaza aid effort “to meet the tortured, persecuted and wronged kinfolk in the strip to assure them that we are with them morally and spiritually,” adding that his goal was “to establish a free, sovereign, independent state, with Jerusalem as its capital.”