The Hague, Netherlands (CNN) -- The chief prosecutor of the International Criminal Court sought the arrest of Libyan leader Moammar Gadhafi and two relatives Monday, linking them to "widespread and systematic" attacks on civilians as they struggle to hold power.

Luis Moreno-Ocampo told reporters his office has "direct evidence" linking Gadhafi, his son Saif al-Islam and brother-in-law Abdullah al-Sanussi to crimes against humanity as longtime Libyan strongman attempts to put down a three-month-old revolt.

Their arrests are "the only way to protect" civilians in areas under the regime's control, Moreno-Ocampo said.

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"The evidence shows that Moammar Gadhafi personally ordered attacks on unarmed Libyan civilians," he said. "His forces attacked Libyan civilians in their homes and in the public space, shot demonstrators with live ammunition, used heavy weaponry against participants in funeral processions and placed snipers to kill those leaving mosques after prayers."

Libya did not sign the treaty that created the International Criminal Court and indicated it would ignore the prosecution move. Governments spokesman Musa Ibrahim denied the allegations and criticized what he called the "incoherent" conclusions of the prosecutor's office.

"We have never in any stage of the crisis in Libya ordered the killing of civilians or hired mercenaries against our people," Ibrahim said. "In fact, it is the rebels who took up arms in the middle of our peaceful cities."

Saif al-Islam is a close adviser to his father, while al-Sanussi serves as Gadhafi's head of intelligence. Saif al-Islam organized the recruitment of mercenaries to defend the regime and al-Sanussi participated in attacks on demonstrators, Moreno-Ocampo said.

Authorities believe Gadhafi "personally ordered" attacks on unarmed civilians, he told CNN, and al-Sanussi is "his right-hand man, the executioner."

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"Gadhafi organized to arrest any suspected dissident, and they tortured them and they disappeared," Moreno-Ocampo said.

Judges on the court must now decide whether to issue the arrest warrants Moreno-Ocampo wants. They have never turned down a request from him in his 10 years with the court, he said.

A panel of judges in The Hague can accept his request, reject it or ask for more evidence. It could take weeks or months for the judges to decide what to do.

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Moreno-Ocampo said senior officials in the Libyan regime have called him in the past few days to offer him their support. He did not name them but indicated that "less than 10" had done so.

Gadhafi has "absolute authority" in Libya, Moreno-Ocampo told reporters. "It's a crime to challenge Gadhafi's authority and he used his authority to commit the crimes."

Monday's move was the first time the International Criminal Court has taken action while a conflict was ongoing. It is the culmination of an investigation that began February 15, when demonstrations against Gadhafi's regime accelerated. Since then, war has erupted in Libya as the strongman has tried to stay firm on his grip on power.

"Gadhafi ruled Libya through fear," Moreno-Ocampo said Monday, "and I think Libyans are losing that fear."

Libyan Deputy Foreign Minister Khalid Kaim dismissed a possible ICC action ahead of Monday's announcement, saying that because Libya is not a signatory of the Rome Statute that established the ICC, the government will "just ignore it."

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The probe took investigators to 11 countries and included the review of 1,200 documents and interviews with about 50 witnesses. A report issued in early May found the alleged crimes against humanity include the alleged commission of rape by supporters of Gadhafi's government, as well as the deportation or forcible transfer of citizens during the civil war in the country.

"It is indeed a characteristic of the situation in Libya that massive crimes are reportedly committed upon instruction of a few persons who control the organizations that execute the orders," the report said. "Arresting those who ordered the commission of crimes, should the judges decide to issue warrants, will contribute to the protection of citizens in Libya."