New York ? The veteran pilot of Continental Airlines Flight 61 who died in mid-flight Thursday had suffered an apparent heart attack, said a doctor who tried to revive the jetliner’s captain.

Dr. Julien Struyven, a cardiologist and radiologist, said he rushed to the cockpit after an announcement over the intercom asked whether a doctor was aboard the Brussels-to-Newark flight.

“When I came in, the pilot was clinically dead,” said Struyven, of Brussels, who has practiced since 1965. He said he used a defibrillator in an attempt to revive the unidentified pilot.

A relief pilot took over the controls after the captain collapsed, and safely landed the Boeing 777 at Newark-Liberty Airport on time at 11:49 a.m., an official for Houston-based Continental said. In addition to the first officer, the flight had a relief pilot on board because of its length.

The captain, 60, apparently died of natural causes, said the official, Kelly Cripe.