Deputy Prime Minister Dmitry Rogozin announced that Russia’s Proton-M rockets will be grounded for more than three months because of engine flaws during production. A report from Kommersant newspaper reports that the Russian space agency has decided to recall the Proton-M engines due to problems. It was revealed during an investigation that the illiquid components used is unable to stand extremely high temperatures.

Rogozin visited the Voronezh Mechanical Plant the company that produces the Proton-M engines and called for an investigation. At least three Proton-M rockets will have to be unassembled and the production process has to be halted. Rogozin wrote that the people who are responsible for the substitution of technology and documentation will be strictly punished.

Rogozin stated the people who allowed the problem to slip through had known perfectly well that their actions could lead to accidents and event death. Rogozin is seeking the toughest internal investigation to be conducted after his meeting with the heads of VMP. The Proton-M launches is set to resume in three and a half months. One launch is scheduled in February.

The Proton-M is a key rocket in Russia’s space program. The rocket is used to make deliveries to the International Space Station. The Proton-M rocket successfully launched an Intelsat 31/DLA-2 communications satellite from the Baikonur Cosmodrome in Kazakhstan last June 2016. The rocket also had its share of incidents over the past years as reported by RT.

After Russian officials put the blame of a crash of a Progress cargo ship in December was a result of a malfunction by engines that were built at the plant, the head of the Voronezh factory resigned. The accident is one of several serious incidents to trouble Russia’s space industry. In May 2015, a Progress cargo ship plunged into the Pacific Ocean. In May of 2014, a Proton-M rocket broke up while carrying an advanced satellite up in the atmosphere as reported by abc NEWS.