LISBON, Jan. 18 (Xinhua) -- The twin sons of Iraq's former ambassador to Portugal have been charged with attempted murder, the Portuguese public prosecution service revealed on Thursday.

The charges relate to an incident that occurred on Aug. 17, 2016 in Ponte de Sor, a rural area 180 km northeast of Lisbon. A brawl left 15-year-old Ruben Cavaco in an induced coma with multiple fractures. He was eventually discharged from hospital in early September.

The Department of Penal Investigation and Action (DIAP) for the district of Evora announced on its website that two young men face charges relating to the incident.

It did not cite names, but the Lusa Portuguese News Agency has confirmed that the defendants are Haider and Ridha Ali, sons of Saad Mohammed Ridha, former Iraqi ambassador.

Aged 17 at the time, Haider and Ridha were arrested following the incident but immediately released. As sons of an ambassador, they had diplomatic immunity.

Portugal has twice asked Iraq to lift their immunity status and allow the boys to testify. But Iraq has failed to comply, raising legal objections and promising to try them in Iraq.

Before his sons left Portugal, the Iraqi ambassador paid 40,000 euros (42,800 U.S. dollars) in compensation to the Cavaco's family and 12,000 euros for treatment expenses for the boy .

Ridha reached an out-of-court compensation agreement on Friday with the family of Cavaco. Iraq withdrew its ambassador from Lisbon in January 2017.

Portugal's Ministry of Foreign Affairs promised on Thursday to make the necessary requests on behalf of the attorney general, via the proper diplomatic channels.