AIR SAFETY EXPERTS WERE PROBING whether an explosion in some luggage or a broken panel punched the hole that forced a Qantas jumbo jet to make an emergency landing at Ninoy Aquino International Airport, a source said Saturday.

The source said the experts were focusing on the two theories as the cause of the rupture on the Boeing 747 as it flew from Hong Kong to Melbourne on Friday with 365 passengers and crew on board. There were no injuries among the passengers and crew.

“While it is too early to say what actually caused the hole, we will be looking at two possibilities … something exploded in one of the bags or a panel came loose on the fuselage,” the source, who is close to the investigation and asked not to be identified for lack of authority to speak, told AFP.

The source said a bomb was unlikely.

Four specialists from the Australian Transport Safety Bureau were inspecting the aircraft yesterday to determine what caused the damage, said retired Gen. Ruben Ciron, director general of the Civil Aviation Authority of the Philippines (CAAP), formerly the Air Transportation Authority.

“They are conducting the investigation. They are the principals, we are just the support,” Ciron said.

An official of the US Transportation Security Administration said initial reports indicated no link to terrorism.

Boeing spokesperson Liz Verdier said the company was providing technical assistance. “We are dispatching four personnel from Boeing, an investigator and three engineers,” she said.

The local Air Transport Office was also looking into the incident, Manila International Airport Authority (Miaa) general manager Alfonso Cusi said.

Cusi said he did not believe an explosion caused the incident, saying “our air safety people are looking into it and from the looks of it, it doesn’t look like an explosion.”

But local bomb experts complained yesterday that restrictions imposed on them prevented them from conducting a deeper investigation of the explosion.

The experts told the Inquirer that Atutubo prevented them from conducting an investigation.

“We were prevented by General Atutubo from getting close to the plane even if it is on Philippine soil. It’s an issue of sovereignty. He (Atutubo) gave us a hard time,” said a bomb expert who spoke on condition of anonymity.