KUALA LUMPUR, Malaysia (AP) — The search for the missing Malaysian jet pushed deep into the northern and southern hemispheres yesterday as Australia scoured the southern Indian Ocean and China offered 21 satellites to respond to Malaysia’s call for help in the unprecedented hunt.

French investigators arriving in Kuala Lumpur to lend expertise from the two-year search for an Air France jet that crashed into the Atlantic Ocean in 2009 said they were able to rely on distress signals. But that vital tool is missing in the Malaysia Airlines mystery because flight 370’s communications were deliberately severed ahead of its disappearance more than a week ago, investigators say.

“It’s very different from the Air France case. The Malaysian situation is much more difficult,” said Jean Paul Troadec, a special adviser to France’s aviation accident investigation bureau.

Malaysian authorities say the jet carrying 239 people was intentionally diverted from its flight path during an overnight flight from Kuala Lumpur to Beijing on March 8 and flew off-course for several hours. Suspicion has fallen on the pilots, although Malaysian officials have said they are looking into everyone aboard the flight.

Malaysian police confiscated a flight simulator from the pilot’s home on Saturday and also visited the home of the co-pilot in what Malaysian police chief Khalid Abu Bakar initially said was the first police visits to those homes. But the Government — which has come under criticism abroad for missteps and foot-dragging in its release of information — issued a statement yesterday contradicting that account by saying police first visited the pilots’ homes as early as March 9, the day after the flight.

Investigators haven’t ruled out hijacking, sabotage, pilot suicide or mass murder, and they are checking the backgrounds of all 227 passengers and 12 crew members, as well as the ground crew, to see if links to terrorists, personal problems or psychological issues could be factors.

For now, though, Malaysian Defence Minister Hishammuddin Hussein said finding the plane was still the main focus, and he did not rule out finding it intact.

“The fact that there was no distress signal, no ransom notes, no parties claiming responsibility, there is always hope,” Hishammuddin said at a news conference.

Malaysian Airlines CEO Ahmad Jauhari Yahya said an initial investigation indicated that the co-pilot, Fariq Abdul Hamid, spoke the fight’s last words — “All right, good night” — to ground controllers. Had it been a voice other than that of Fariq or the pilot, Zaharie Ahmad Shah, it would have clearest indication yet of something amiss in the cockpit before the flight went off-course.

Malaysian officials earlier said those words came after one of the jetliner’s data communications systems — the Aircraft Communications Addressing and Reporting System (ACARS) — had been switched off, sharpening suspicion that one or both of the pilots may have been involved in the plane’s disappearance.

However, Ahmad said yesterday that while the last data transmission from ACARS — which gives plane performance and maintenance information — came before that, it was still unclear at what point the system was switched off. That opened the possibility that both ACARS and the plane’s transponders — which make the plane visible to civilian air traffic controllers — were severed later and at about the same time. It also suggests that the all-clear message delivered from the cockpit could have preceded any of the severed communications.

SEPANG, Malaysia — Malaysia’s acting Transport Minister Hishamuddin Hussein shows maps of the northern search corridor during a press conference at a hotel near the Kuala Lumpur International Airport, in Sepang yesterday. Twenty-six countries are involved in the massive international search for the Malaysia Airlines jetliner that disappeared on March 8 with 239 people aboard. (PHOTO: AP)