AMSTERDAM (Reuters) - Libya said on Tuesday it would complete its investigation into Muammar Gaddafi's son, Saif al-Islam Gaddafi, within weeks for crimes including murder and torture, and asked the International Criminal Court once again to hold off ordering his surrender.
Libya's government and the war crimes court - which indicted Saif al-Islam in June for crimes against humanity stemming from the crackdown on last year's revolt - have argued for months over where he should be tried.
Tripoli considers it a matter of national pride and a measure of the country's transformation for Saif al-Islam's trial to be held in Libya.
But human rights groups question whether its justice system can meet the standards of international law and say he should be handed over to the ICC instead.
According to a document released by The Hague-based court on Tuesday, the Libyan government once again challenged the admissibility before the ICC of the cases concerning both Saif al-Islam and Abdullah al-Senussi, Gaddafi's intelligence chief.
"The Libyan government regards the trial of Mr Gaddafi and Mr Al-Senussi as a matter of the highest national importance, not only in bringing justice for the Libyan people but also in demonstrating that the Libyan justice system is capable of proper investigation and prosecution, and that it can conduct fair trials," the government said in the document.
It said its own investigations "are now at an advanced stage" and "are expected to be completed in the near future".
"It is anticipated that the investigative phase of proceedings with respect to Mr Gaddafi will be completed within the next few weeks," the government added, whereas for Senussi, the proceedings would take longer because he is not in the country.
Senussi was arrested in Mauritania in March and is wanted by Libya, France and the ICC.
Libya said Senussi is under investigation for crimes which it says took place during 2011, such as the shooting of captured rebels who were no longer able to fight.
He is also investigated for "other serious crimes" which took place before the revolution, including the massacre of 1,270 prisoners at Abu Selim prison on June 27, 1996 after they complained about poor treatment, according to the court document.
"Statements of six eyewitnesses have been taken in relation to this incident and these statements attest to the personal involvement of Mr Al-Senussi in the mass killing that day," the Libyan government said in the court document.
It added that Saif al-Islam and Senussi were also being investigated for various financial crimes.
Senussi's poor health has held up his extradition from Mauritania to Libya, according to the court document.
"Mr Al-Senussi's liver disease has become apparent and his health condition is now such that it is understood that he cannot presently be investigated domestically for breaches of Mauritanian law, let alone transferred back to Libya," the government said in the court document.
"The justice ministries of both countries are in regular contact and are monitoring Mr Al-Senussi's condition in order to determine when his transfer will be possible," it added.
Libya also refuted allegations that Saif al-Islam had been physically attacked and misled over the charges against him, saying he had been provided with proper medical and dental care and had not been physically abused.
"Mr Gaddafi has been kept in adequate conditions of detention (which will be improved even further upon his transfer to newly constructed prison facilities in Tripoli), provided with sufficient and good quality food (the same food as that consumed by his prison guards)," it said in the document.
(Reporting by Sara Webb; Editing by Michael Roddy/Maria Golovnina)