One theory is that a damaged wheel on a truck caused the driver to swerve into the oncoming lane, colliding with a minibus.
Other possible factors being investigated include defective vehicles allowed on the road by transport company officials, driver negligence, traffic rule violations, and unforeseeable circumstances.
Specialized experts have analyzed the accident scene, and 18 investigations have been commissioned, including automotive and forensic evaluations and alcohol tests. Witnesses to the accident have also been interviewed.
This follows an earlier report by Ukrainian Interior Minister Ihor Klymenko on July 6, detailing the collision between a tanker truck and a minibus in Rivne Oblast that killed 14 people, including a 6-year-old child.
Only one woman survived, and doctors are fighting for her life.