US Edition • Father-of-seven from Manchester reportedly shot dead
• Gaddafi to be investigated by ICC over crimes against humanity
• Gaddafi forces strike oil export hubs in Brega for second day
• Dmitry Medvedev warns of "civil war"
In an interview with Sky News, Saif said: "First of all the bombs (were) just to frighten them to go away. Not to kill them.
"I'm talking about the harbour and the oil refinery there. Nobody would allow the militia to control Brega. It's like allowing someone to control Rotterdam harbour in Holland.
His comments came as the International Criminal Court announced that Col Gaddafi and key aides will be investigated over allegations they committed crimes against humanity while fending off the uprising in Libya.
Luis Moreno-Ocampo, the Hague's prosecutor said: "We have identified some individuals with de facto or formal authority, who have authority over the security forces.
"They are Muammar Gaddafi, his inner circle, including some of his sons."
He also listed individuals including the veteran Libyan leader's head of personal security, and head of external security forces, adding there would be "no impunity in Libya".
The announcement came amid reports a father-of-seven from Manchester has been shot dead in Libya.
Friends of Khaled Attghdi, from Whalley Range, said he had been killed in the oil port of Brega on Wednesday. Relatives said he had travelled to Libya last week to help relatives caught up in the unrest.
The Foreign Office said it was aware of the reports and was "urgently investigating" them.
Forces belonging to Muammar Gaddafi meanwhile struck oil export hubs in Brega for the second day.
Witnesses said a warplane bombed the eastern oil terminal town of Brega, a day after troops loyal to Gaddafi launched a ground and air attack on the Libyan town that was repulsed by rebels spearheading a popular revolt against his four-decade-old rule.
The rebels, armed with rocket launchers, anti-aircraft guns and tanks, called on Wednesday for UN-backed air strikes on foreign mercenaries it said were fighting for Gaddafi.
Dmitry Medvedev, the Russian president, warned that Libya is on the verge of civil war, calling it an "extreme situation".
"Libya was an is on the verge of civil war and our main task was to save our people there (Russian citizens)," he said, praising an operation to evacuate Russians from Libya.
The uprising, the bloodiest yet against long-serving rulers in the Middle East and North Africa, is causing a humanitarian crisis, especially on the Tunisian border where tens of thousands of foreign workers have fled to safety.
As the struggle between Gaddafi loyalists and rebels who have taken swathes of Libya intensified, Gaddafi, as well as the Arab League, said they had accepted a peace plan for Libya from Venezuela's President Hugo Chavez.
Hillary Clinton, the US secretary of state, said in Washington that one of the biggest US concerns was "Libya descending into chaos and becoming another Somalia".