Two high-ranking Libyan air force pilots have who fled to Malta in their aircraft are reported to have told officials they escaped rather than carry out orders to bomb civilians.

The officers defected as Libyan diplomats in several countries and international organisations resigned in protest at the regime's violent response to the deepening crisis. They included Muammar Gaddafi's ambassadors to China, India, Indonesia and Poland, as well as Libya's representative to the Arab League and most, if not all, of its mission at the United Nations.

Omar Jelban, head of the London People's Bureau, flatly denied an al-Jazeera report he too had quit. Jelban was earlier called to the Foreign Office to hear what William Hague, the foreign secretary, called "our absolute condemnation of the use of lethal force against demonstrators".

The two Mirage F1 jets touched down in Malta after the pilots said they urgently needed to refuel and sought emergency clearance to land. The Times of Malta reported on its website the pilots had told officials they flew to the island after being ordered to bomb protesters occupying Libya's second-biggest city of Benghazi.

One report said they had also brought with them two other members of the Libyan armed forces. The pilots – both colonels – said that, after taking off from Okba Ben Nafi base, they flew low through Libyan air space to avoid radar detection.

The pilots were being questioned by Maltese police who were also trying to identify seven other people who landed from Libya in two civilian helicopters shortly before the arrival of the jets. The helicopters took off from Libya without official clearance and a source in Malta said they appeared to have been in haste, with only one of the seven people aboard carrying a passport.

All seven said they were French. The helicopters' passengers said they were working on an oil platform off Benghazi when the violence in Libya erupted.

The two military jets were at Malta international airport near Valletta, away from the commercial area.

A spokesman for Libya's delegation at the UN told Reuters its members had declared their allegiance to Libya's people, not the government. The spokesman, Dia al-Hotmani, said: "The members of the Libyan mission are representing only the Libyan people and not anyone else."

The deputy UN ambassador told the BBC: "All the Libyan people want Gaddafi to go." Other members of the UN mission had said they were resigning to support anti-government protesters: "We are aware that this will put our families back home in danger, but they are in danger anyway," said member Adam Tarbah.

In New Delhi, Ali al-Essawi accused his government of deploying foreign mercenaries against protesters. And three local employees of the Libyan embassy in Sweden said they had quit in protest.

"It would be hypocritical to assist the Libyan government while we see them attacking people in the streets," said Sayed Jalabi.