THE HAGUE - The International Criminal Court issued arrest warrants on Monday for Libya's Muammar Gadhafi, his son Saif al-Islam and the country's spy chief, Abdullah al-Senussi, on charges of crimes against humanity.

ICC prosecutor Luis Moreno-Ocampo had in May asked the court to issue arrest warrants for the "pre-determined" killing of protesters in Libya after the UN Security Council referred the issue to the court.

Gadhafi has "absolute, ultimate and unquestioned control" over Libya's state apparatus and its security forces, presiding judge Sanji Mmasenono Monageng said in reading out the ruling.

She added that both Gadhafi and Saif al-Islam "conceived and orchestrated a plan to deter and quell by all means the civilian demonstrations" against the regime and that al-Senussi used his position of command to have attacks carried out.

Gadhafi, who has run his oil-producing Arab North African country since a military coup in 1969, is under pressure to relinquish power from rebels who rose up against his rule and from a NATO bombing campaign.

But more than three months into the NATO campaign, fissures are showing within the Western alliance and it is feared that the ICC warrant could also trigger greater violence in Libya as Gadhafi tries to cling to power.

In its ruling, the ICC said there was "reasonable grounds" to believe that Gadhafi, his son and al-Senussi committed crimes within the jurisdiction of the court and that a warrant for their arrest should be issued.

This was the second warrant of arrest issued by the ICC against a sitting head of state -- following two slapped on Sudanese President Omar al-Bashir in 2009 and 2010 for crimes against humanity, war crimes and genocide in Darfur.

Securing arrests, however, has proven difficult for the ICC. It has no police force and relies on member states to enforce arrest orders. The civil war in Libya is likely to complicate attempts to enforce the court's latest warrants.

In arguing for warrants, Moreno-Ocampo said Gadhafi drew up a plan to quell protests through the use of "extreme and lethal violence" and that all three men implemented a state policy of "widespread and systematic attacks" on civilians.

Gadhafi's government denies targeting Libyan civilians, accusing NATO of doing so.

"Crimes continue today in Libya. To stop the crimes and protect civilians in Libya, Gadhafi must be arrested," Moreno-Ocampo said in a statement on Sunday ahead of the ruling.