A senior airline official representing the Russian airline Kogalymavia has blamed Saturday’s Sinai plane crash on an “external influence,” according to CNN. The crash killed all 224 people that were on board.

The official added that planes don’t just fall apart in midair, but that’s exactly what happened to Kogalymavia Flight 9268 before it crashed into a remote area of Egypt’s Sinai Peninsula.

The executive did not release details on what he meant by an external influence, but an investigation is underway. Aviation experts on currently looking through the data on the airplane’s “black boxes,” but no results have been shared yet.

BBC News reports that the head of Russia’s Federal Aviation Agency stated that it is too early to know the cause of the crash, despite what the senior airline official has said.

“It is completely premature to speak about the reasons of this, as there are not grounds. And I’d like to call on the aviation community to refrain from any premature conclusions,” Sputnicknews.com quoted Alexander Neradko, the agency chief, who talked to Rossiya-25 television.

CNN aviation analyst Peter Goelz said that because the plane broke into several pieces before hitting the ground, that it helps reduce to the list of possible causes, however, there are still plenty of situations that could have happened.

Here are the only facts that are concrete at this time: the airplane came apart mid air, the plane lost speed and began to descend quickly, and the crew made no attempts to contact any sort of air traffic control to report the situation.

AP reports that Russian Emergency Situations Minister Vladimir Puchkov stated that the crash site would continue to be searched until all the bodies of the victims were found. Currently, 144 bodies have been sent to St. Petersburg and more are expected to arrive Monday evening.

According to CNN, 217 people on the plane were passengers and 7 were crew members. Of the passengers, 25 were children.

Russian President Putin expressed his condolences to the victim’s families.

“This is a terrible tragedy and we are most certainly with you at this time with all our hearts and souls,” Putin said.

“I want to thank the people of St. Petersburg for the way they have responded. The whole country has seen this, everyone in Russia, and I want to thank you for your words of sympathy and condolence. In such tragic hours, it is certainly very important to feel the support of those close to you and know you have the entire country’s sympathy over this terrible disaster.”

The United States, Germany, and Britain all issued overflight warnings for the Sinai Peninsula previous to the crash due to extremist violence in the area. Germany issued the warnings on October 5 while America and Britain issued the warnings on October 15.