The crew of the Soyuz capsule that landed in Kazakhstan hundreds of miles off-target after an unexpectedly severe descent was in serious danger, a Russian news agency reported Tuesday.

Interfax quoted an unidentified space official as saying that the capsule entered the atmosphere improperly, with the hatch first, instead of with its heat shields leading the way.

As a result, the capsule suffered significant damage.

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The official also says the TMA-11 capsule's antenna burned up during the descent, meaning the crew couldn't communicate properly with Russian Mission Control.

Interfax said the official was involved in the investigation into the causes of the Saturday landing.

The Soyuz crew included South Korea's first astronaut, Yi So-yeon, U.S. astronaut Peggy Whitson and Russian flight engineer Yuri Malenchenko.

"The fact that the entire crew ended up whole and undamaged is a great success. Everything could have turned out much worse," the official was quoted as saying. "You could say the situation was on a razor's edge."

Alexander Vorobyov, a spokesman for the Russian Federal Space Agency, confirmed that the descent had problems, saying that the Soyuz hatch and the antenna did suffer partial burn damage, but said that was a common occurrence when the capsules re-enter the Earth's atmosphere.

He said investigators looking into Saturday's landing had classified it as a "3" on the 5-point scale of seriousness, where "5" would be a critical level.

Russian officials were still investigating what went wrong, he said.

The crew was returning from the international space station and endured severe gravitational forces because the capsule took a steeper-than-usual re-entry, called a "ballistic trajectory."

The capsule ended up landing some 260 miles off-target and was 20 minutes late.

On Monday, Yi told a news conference at the Star City cosmonaut training center outside of Moscow that she was frightened by the descent.

"At first I was really scared because it looked really, really hot and I thought we could burn," she told reporters.

The incident was the second time in a row — and the third since 2003 — that a Soyuz landing had gone awry.

A NASA spokesman said the U.S. space agency was in communication with the Russians about the capsule's off-target landing.

John Yembrick said NASA was reserving comment until the Russians get to the cause.

"We're being cautious and waiting until the Russians gather the data," he said.

Despite the problems, the Russian space program has had a reputation for reliability.

The single-use Soyuz and Progress vehicles have long been the workhorses of the space-station program, regularly shuttling people and cargo to the orbiting outpost.

They took on greater importance following the grounding of the U.S. space shuttle fleet in the wake of the 2003 Columbia disaster.