SpaceX CEO has explained the most-likely cause of last month’s Falcon 9 explosion. He said a faulty steel strut may have caused the explosion of the rocket two minutes after its take-off from Cape Canaveral.

Musk said while making his first public comments on the disaster that the strut was probably not made the way it should have been and there was no way out to figure out that by simply looking at it from outside.

Falcon 9 explosion last month added the third explosion of a rocket in the string of mission failures to the ISS in 12 months. Previously, Russia’s Progress 59 mission burnt after it was lost in orbit and Russia’s Progress 59 mission exploded in October 2014.

The Falcon 9 rocket explosion was believed to be the result of an overpressure event in the Second Stage 139 seconds after liftoff. This led to the loss of Dragon and the disintegration of the Falcon 9 launch vehicle.

After the explosion, SpaceX worked hard to determine what led to the disaster and collected remaining items of the destroyed Falcon 9.

Musk said the helium tank floats in oxygen and its buoyancy increases proportionate to the loading. However, overpressure ruptured the tank and the rocket disintegrated soon after the liftoff.

“Obviously, what we’re going to do in the future is not use these particular struts, and we’re going to move to individually testing each strut independent of any material certifications”, said Musk.