Boeing has suspended testing on its 777x aircraft after a faulty cargo door failed in a ground stress test, Reuters reported, citing a statement from a company spokesman.

“During final load testing on the 777X static test airplane, the team encountered an issue that required suspension of the test,” Reuters quoted the spokesman as saying.

The Seattle Times reported a cargo door exploded outward during a high-pressure stress test on the ground. The newspaper said the accident occurred on a static test airplane, which is built for ground testing only and not intended to fly.

In final load testing, planes are subjected to loads and stresses that are well beyond normal operational conditions, the spokesman said, adding that the incident is under review.