us_marine_helicopter_410px_As tensions mount on the Korean peninsula, a U.S. helicopter crashed yesterday (16) near South Korea’s border with the North while conducting routine flight operations.

All 21 people aboard the helicopter survived. Sixteen soldiers were released from hospital and 5 were hospitalized in stable condition.

The exact cause of the crash is not yet known, but the incident occurred during ongoing South Korea-U.S. joint military exercises.

Meanwhile, American Airlines had to ground all its flights across the US for several hours yesterday (16) due to a fault with its computerised reservation system.

American fixed the problem three hours later, but warned that it expected to see delays and cancelations continue for the remainder of the day. About 900 flights were affected.

American said it would offer refunds and allow passengers to change flights for free, BBC reports.