United Nations (CNN) -- Mercenary forces may be trying to help Moammar Gadhafi's son escape Libya, even as people linked to Saif Al-Islam Gadhafi have been in contact with the International Criminal Court about his possible surrender, ICC Chief Prosecutor Luis Moreno-Ocampo said Wednesday.
In a report to the U.N. Security Council on the Libya situation, Moreno-Ocampo also said "hundreds of rapes" occurred in the Libyan conflict this year that toppled Moammar Gadhafi's 42-year-rule and resulted in his capture and killing last month.
Investigations continue into reported atrocities by Libyan forces, mercenaries and anti-government forces, Moreno-Ocampo said. In addition, the reported deaths of Libyan civilians in NATO airstrikes also will be examined, his report said.
"There are more allegations," Moreno-Ocampo said. "There are serious allegations against multiple actors."
His report called on U.N. states to "do all they can to disrupt" any attempt to help Gadhafi or former Libya intelligence chief Abdullah al-Senussi get away.
Both men are charged by the ICC with crimes against the Libyan people during the conflict.
"It is up to Saif Al-Islam Gadhafi and Abdullah al-Senussi to decide if they will surrender themselves, remain in hiding or try to escape to another country," Moreno-Ocampo said in the report. "It is up to the U.N. Security Council and the states to ensure that they face justice for the crimes for which they are charged."
While offering no details of contacts with anyone linked to Saif Al-Islam Gadhafi, Moreno-Ocampo said the ICC had offered him the possibility of safe transfer to The Hague to stand trial with legal representation.
"We cannot negotiate," Moreno-Ocampo said. "We offered him what we can offer him."
He was unable to say where Gadhafi is now.
The U.S. ambassador to the United Nations, Susan Rice, said Gadhafi and al-Senussi "must be brought to justice in a legitimate process governed by the rule of law."
On the rape allegations, Moreno-Ocampo's report said some witnesses indicated Moammar Gadhafi and al-Senussi had discussed "the use of rape to persecute those considered dissidents or rebels," but that it was too soon to determine "who may be the most responsible for such gender crimes."
Meanwhile, Bosnia's U.N. ambassador called Wednesday for an independent investigation of Moammar Gadhafi's death after being captured by opposition forces.
Libya's National Transitional Council has promised to examine what happened, but the statement by Ambassador Ivan Barbalic said the investigation must be seen as impartial, adding: "The rule of law should be a cornerstone of the new rebuilt country."
CNN's Tom Cohen contributed to this report.