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A Continental Airlines jetliner carrying 247 passengers landed in Newark shortly before noon on Thursday, after the flight’s captain died midflight.

Two first officers took control of the plane, a Boeing 777, after the captain, who was 60 years old, “died in flight, apparently of natural causes,” according to Julie King, a spokeswoman for Continental. The captain had 32 years of service with Continental and was based in Newark, she said, adding that his family had been notified.

The flight, Flight 61, took off at 9:54 a.m. in Brussels (3:54 a.m. Eastern time), according to Continental’s Web site. It touched down at 11:47 a.m., earlier than its scheduled noon landing, at Gate C123 at Newark Liberty International Airport.

Marlyse Isacson, who lives in Belgium and was flying to the United States to visit relatives, said that five people — four men and one woman — went up to the front of the plane after a call for a doctor was made over the plane’s public-address system about halfway through the flight. Four of them later returned.

The passengers were not told of the emergency. “We asked the stewardesses and they said ‘someone fell ill,'” Ms. Isacson recalled. She said the only thing even the slightest bit unusual was “some of the staff were very irritated and unpleasant.” When the plane landed on the tarmac, for example, the flight attendants sternly warned the passengers to remain seated. “Now I understand why,” Ms. Isacson added.

A Belgian cardiac radiologist, Dr. Julien Struyven, 72, checked the pilot’s vital signs and declared him dead. Dr. Struyven told reporters that he tried to use a defibrillator on the plane, but was not able to revive the pilot. Dr. Struyven said a heart attack was the likely cause of death.

Passengers had no idea what happened until the plane landed. “It’s scary, but in all honesty, it’s kind of good that they didn’t tell us,” said Chris Balchuns, 18, a passenger on the flight. “Everybody kept calm.”

Martha Love, who was seated in the front row of the plane, said there was no panic. “It was very calm,” she said. “Everyone was very relaxed.”

Another passenger, Kathleen Ledger of Bethlehem, Pa., who was returning from a visit to her husband in Brussels, said she turned on her cellphone after the plane had landed and spoke to her husband, who relayed the news.

After the pilot’s death, his body was taken from the cockpit to the crew rest area, according to Les Dorr Jr., a spokesman for the Federal Aviation Administration. Mr. Dorr said the plane was on auto-pilot at the time the pilot died.

Ms. King said that two other pilots — a reserve officer and a first officer — assumed the controls. “The crew on this flight included an additional relief pilot, who took the place of the deceased pilot,” she said. “The flight continued safely with two pilots at the controls. The company has been in touch with his family and we extend our deepest sympathies.”

Federal authorities received notification of the emergency at 10:30 a.m. As of 11 a.m., the plane was in the skies over Canada, having followed its route south over Newfoundland. Information was reported to federal aviation officials from the air-traffic system on the ground, which was communicating directly with the cockpit, said Arlene Salac, an F.A.A. spokeswoman.

Steve Coleman, a spokesman for the Port Authority of New York and New Jersey, which operates the region’s airports, said that at the request of the F.A.A. control tower, “we rolled the emergency equipment as a precaution.” Fire trucks and other equipment assembled on the tarmac, but they were not necessary, he said.

In 2007, Congress voted unanimously to increase the mandatory retirement age for commercial pilots from 60 to 65, the international standard, changing a Federal Aviation Administration regulation that had been in place since 1960. The argument for the age limit is that older pilots more frequently become incapacitated for medical reasons.

Under the new law, known as the Fair Treatment for Experienced Pilots Act, pilots ages 60 and above are required to have a medical certificate renewed every six months. The legislation also included a stipulation for international flights: a pilot who has turned 60 may be the pilot-in-command only if there is another pilot in the flight crew who is younger than 60.

Amy Flanagan, a spokeswoman for the Air Line Pilots Association, said that the captain typically does not do all the flying on a transatlantic flight, and that first officers are required to do some takeoffs and landings to fill requisite hours.

In an emergency, if it becomes clear that the captain has become incapacitated, the first officer would be expected to first take control of the aircraft, and then seek help.

There have been previous instances of pilots dying during flights.

In April 2009, a passenger landed a privately operated twin-engine plane at Southwest Florida International Airport, in Fort Myers, saving four lives, when the pilot died after takeoff. The passenger, Doug White, who owned the plane and whose family was aboard, had experience flying only single-engine planes, but landed the plane safely with the help of traffic controllers.

In February 2008, a British Airways flight operated by GB Airways, which had left Manchester, England, heading for Paphos, in Cyprus, was diverted to Istanbul after one of the first officers died. None of the 156 passengers was hurt.

In January 2007, a pilot of a Continental 757 bound from Houston to Puerto Vallarta, Mexico, died after takeoff, with 210 passengers were on board. The flight landed safely after being diverted to McAllen-Miller International Airport in Texas.

Liz Robbins and A. G. Sulzberger contributed reporting from New York, and Nate Schweber and Dominick Tao from Newark.