(PIX11/CNN) — Malaysia Airlines said Saturday that it has lost contact with a passenger flight carrying 227 passengers and 12 crew members en route to Beijing. Four of those passengers are U.S. citizens — three adults and an infant — officials said Friday night.

According to a statement from the airlines:

“[#MASalert] Statement By Our Group Chief Executive Officer, Ahmad Jauhari Yahya on MH370 Incident. Released at 9.05am/8 Mar 2014 MY Local Time

We deeply regret that we have lost all contacts with flight MH370 which departed Kuala Lumpur at 12.41 am earlier this morning bound for Beijing.

The aircraft was scheduled to land at Beijing International Airport at 6.30am local Beijing time.

Subang Air Traffic Control reported that it lost contact at 2.40am (local Malaysia time) today.

Flight MH370 was operated on a Boeing B777-200 aircraft.

The flight was carrying a total number of 239 passengers and crew – comprising 227 passengers (including 2 infants), 12 crew members. The passengers were of 13 different nationalities.

Malaysia Airlines is currently working with the authorities who have activated their Search and Rescue team to locate the aircraft.

Our team is currently calling the next-of-kin of passengers and crew.

Focus of the airline is to work with the emergency responders and authorities and mobilize its full support.

Our thoughts and prayers are with all affected passengers and crew and their family members.

The airline will provide regular updates on the situation.

The public may contact +603 7884 1234. For media queries, kindly contact +603 8777 5698/ +603 8787 1276.”

“At the moment we have no idea where this aircraft is right now,” Malaysia Airlines Vice President of Operations Control Fuad Sharuji told CNN’s “AC360.”

The jet was carrying about 7.5 hours of fuel and would likely have run out of fuel, he said.

Efforts to contact the plane were fruitless.

“We deeply regret that we have lost all contacts” with the jet, said CEO Ahmad Juahari Yahya in a statement.

Reaction of people in Beijing Airport after reports of missing Malaysia Airlines jet. http://t.co/tvqlPCNNO0 pic.twitter.com/CzXXlbzG9Q — Jim Roberts (@nycjim) March 8, 2014

The airline said in a statement that its representatives were contacting the relatives of those aboard. “Focus of the airline is to work with the emergency responders and authorities and mobilize its full support,” it said.

“We’re closely monitoring reports on Malaysia flight MH370,” Boeing said in a tweet. “Our thoughts are with everyone on board.”

“It doesn’t sound very good,” retired American Airlines Capt. Jim Tilmon told CNN’s “AC360.” He noted that the route is mostly overland, which means that there would be plenty of antennae, radar and radios to contact the plane.

“I’ve been trying to come up with every scenario that I could just to explain this away, but I haven’t been very successful.”

He said the plane is “about as sophisticated as any commercial airplane could possibly be,” with an excellent safety record.

There is one recent blemish: An Asiana Airlines Boeing 777 carrying 291 passengers struck a seawall at San Francisco International Airport in July 2013, killing three people and wounding dozens more.

China’s state-run Xinhua News Agency reported that Chinese aviation authorities had confirmed that 160 Chinese nationals were aboard the plane, which was lost from radar in airspace controlled by Vietnam.

We’re closely monitoring reports on Malaysia flight MH370. Our thoughts are with everyone on board. — Boeing Airplanes (@BoeingAirplanes) March 8, 2014

China’s embassy in Malaysia has formed an emergency team headed by the Chinese ambassador to deal with the incident, it said.

Malaysia Airlines operates in Southeast Asia, East Asia, South Asia, the Middle East and on the route between Europe and Australasia.

The airline’s roots date back to 1937, when it operated passenger and cargo flights in Malaysia.

In April 1942, it was incorporated as Malaysia Airways Limited; it later became Malaysia Airlines.

The airline has its headquarters and registered office at Sultan Abdul Aziz Shah Airport in Subang, Malaysia, and its main airline hub is at Kuala Lumpur International Airport, according to its website.