CBS News Correspondent Barry Petersen reports the emergency came up so suddenly, the pilot had no time to alert those aboard of the quick maneuver that had to be done to avoid crashing into the other plane.
"I have never seen a plane fly so close," an unidentified passenger told the Japanese television network NHK. "I thought we were going to crash."
The injured were on Japan Airlines domestic flight 907 from Tokyo's Haneda airport to Naha, on the southern Japan island of Okinawa, according to Haneda spokeswoman Yuki Kobayashi.
Kobayashi says the Boeing 747-400, which left for Naha late Wednesday afternoon carrying 411 passengers and 16 crew members, returned safely to Haneda. The other plane, a Japan Airlines flight from Pusan, South Korea, carrying 236 passengers, also landed safely.
The injuries were mostly bruises. But three passengers, including a 54-year-old woman with a broken leg, were in serious condition, according to Japan Airlines spokesman Takeshi Suzuki.
Two American teen-agers - Meggan Wesche, 15, and Allison Ambrose, 14, both of Michigan state - were briefly hospitalized before being released with minor injuries. Hospital official Yumiko Ishida said the girls were on their way to Kadena Air Base on Okinawa, where their parents are stationed.
"I express my deepest regrets," said Japan Airlines Vice President Yasushi Yuasa, at a news conference.
The pilot, Makoto Watanabe, 40, reported 15 minutes into the flight that a collision warning device had gone off in the cockpit and that he was taking emergency action to avoid the other aircraft and would immediately descend from an altitude of 37,000 feet.
Yuasa said the alarm is set to go off 25 to 40 seconds before an imminent crash if measures are not taken to change course.
The emergency developed when the two planes were about 280 miles southwest of Tokyo.
According to the flight plan, the planes' courses were to cross, but with 2,000 feet between them. Yuasa said it wasn't known how close they actually came, however.
Yuasa also added that two training pilots were in the cockpit, and said it wasn't clear if Watanabe had been at the controls before the evasive action was taken.
One passenger from Flight 907 says people were lifted out of their seats by the force of the plane's sudden descent, hitting the ceiling of the cabin.
Another told Fuji Television that he saw the second plane ascending fast while the plane he was on suddenly descended.
Other passengers say the plane rocked back and forth violently.
Several passengers were taken to ambulances on stretchers, and others had bandages on their heads.
The other plane, Japan Airlines flight No. 958 on its way to Narita airport from Pusan, in South Korea, landed at Narita, Tokyo's interational airport. Narita is about 60 miles east of Haneda.
There were no injuries on the other plane, a DC-10 with 236 passengers aboard, said JAL official Mineo Moro. He said the number of crew on that flight was not known.
The airline and the Transportation Ministry are investigating the cause of the accident and are questioning the pilots.
A government official quotes the pilot of Flight 958 as saying he was not aware of the near-collision.
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