South Korea ? A South Korean rocket carrying a climate observation satellite apparently exploded 137 seconds into its flight early Thursday, the country’s second major space setback in less than a year.

The two-stage Naro rocket operated normally during and after liftoff from the country’s space center, Minister of Education, Science and Technology Ahn Byong-man said. But then communications with the rocket were lost after it reached an altitude of about 43 miles.

“We believe that the Naro rocket is likely to have exploded,” he told reporters. “We are sorry for failing to live up to people’s expectations.”

An image from a camera aboard the Naro brightened like a flash of light, possibly evidence of an explosion, Ahn said.

He said South Korean and Russian experts were trying to find the cause of the mishap. The first stage of the rocket was designed and built by Russia and the second by South Korea.