Rescue crews are expanding air and sea search efforts for missing Malaysia Airlines Flight 370. Officials say the oil slicks spotted by crews in the South China Sea do not belong to the plane. Reports of floating wreckage turned up to be a false lead.

Texas-Based Company Says 20 Employees Were on Missing Flight

Air controllers lost contact with the Boeing 777 on Friday about an hour after takeoff from Kuala Lumpur to Beijing. Two of the 239 passengers on board used stolen passports.

Investigators have considered the possibility of terrorism, but remain inconclusive.

Sunday on America’s News HQ, Congressman Peter King (R-NY) noted that Malaysia has been a hub for Al Qaeda in the past.

Fox News chief intelligence correspondent Catherine Herridge said the focus now is on the stolen passports. The individuals are being identified through the security checkpoint video and three flight screening stations. Those images are being cross-referenced against criminal and terrorist databases. reports:

Interpol said it knew about the stolen passports but said no authorities checked its vast databases on stolen documents before the Boeing jetliner departed Saturday.

Warning "only a handful of countries" routinely make such checks, Interpol secretary general Ronald Noble chided authorities for "waiting for a tragedy to put prudent security measures in place at borders and boarding gates."

The thefts of the two passports -- one belonging to Austrian Christian Kozel and the other to Luigi Maraldi of Italy -- were entered into Interpol's database after they were stolen in Thailand in 2012 and last year, the police body said.

Electronic booking records show that one-way flight tickets with those names were issued Thursday from a travel agency in the beach resort of Pattaya in eastern Thailand. A person who answered the phone at the agency said she could not comment.

Officials emphasize that this is a part of the world where human smuggling is rampant, which may explain the stolen passports.

Herridge reported that the National Transportation Safety Board sent a team to assist with the investigation. Technical advisors from the FAA will also help assess the final contact with the aircraft and maintenance records.

It took investigators five days to find the first parts of the Air France plane that crashed into the Atlantic Ocean near Brazil in 2009.