The first trial of a senior official in the Muammar Gaddafi's regime since rebels won a decisive victory in last year's war has opened.
The trial of Buzeid Dorda, a former Gaddafi intelligence chief which began on Tuesday, will be seen as a test of the Libyan government's ability to try high profile loyalists and family members of the deposed leader.
Under heavy security, Dorda, arrested last September in Tripoli, appeared in the dock in the first such civilian hearing since last year's uprising.
Judge Al-Ajaily Al-Maaloul read six charges against him - conspiring to kill civilians, providing weapons for the purpose of killing civilians, conspiring to provoke civil war, denying people their right to protest, unlawful detention and abuse of authority.
"I deny all these points. I will supply the evidence when I testify in court," Dorda said.
The judge adjourned the trial until June 26, as demanded by defence lawyer Dhao Al-Mansouri Awon, who said he and his client needed more time to study the case files.
Wearing a blue prison inmate uniform, Dorda walked into the court using two canes.
Officials said he had injured his legs about two months ago when he tried to escape and fell from a second floor window.
He was treated in hospital, they said.
Dorda had been with Gaddafi since he first seized power in a 1969 coup. He was known as a technocrat, not an intelligence officer by training.
Libyans do not associate him with some of the earlier and bloodiest periods in Gaddafi's autocracy such as the 1980s, reports Reuters news agency.
He is believed to have taken on his job in 2009.
Members of his family attended the trial, including his brother Abdullah, who had visited Dorda on Friday and said he was still in pain from his leg injury.
"I am sure that a Libyan judge will give my brother a fair hearing," he said.
Libya's new rulers are keen to try Gaddafi's family members and loyalists at home, but human rights activists worry that a weak central government and a lack of rule of law could rob them of the right to a fair trial.
Libya wants to try Gaddafi's son Saif al-Islam, who was captured in November and is also wanted by the International Criminal Court (ICC) in The Hague.
If the ICC rules Libya is unwilling or unable to try Saif al-Islam, who is accused of crimes against humanity over the killing of civilian protesters, it says it will take jurisdiction of the case.