MEXICO CITY (AP) — The main points of a comprehensive report about the disappearance in Mexico of 43 college students released Sunday by an independent group of experts from the Inter-American Court on Human Rights:

The government has said there were three attacks on teachers' college students hijacking buses in the city of Iguala in southern Guerrero state. But the report says there were nine attacks, "each progressively more aggressive," leaving six dead, 43 disappeared and another 40 injured. It says that 180 people had their human rights violated in some form.

The government says the attacks were a case of mistaken identity and carried out by local police working for the Guerrero Unidos drug cartel. But the report says federal and state police, plus the military, knew before the students arrived in Iguala who they were and were present in at least two crime scenes, but never stopped local police from shooting at unarmed civilians.

The government says the police thought the students were rival cartel members. The report says the most likely explanation for the viciousness of the attacks was that students inadvertently hijacked a bus linked to the movement of heroin or cash in a city known as a drug transport hub to the United States. The contraband is often moved in buses, and one bus in question disappeared from the official investigation, even though the students mentioned it from the start.

The government says the students were shot and then burned in a giant funeral pyre that lasted for hours in a municipal garbage dump in nearby Cocula. The report cites an independent international fire expert who said such an act would be impossible, and the evidence from the scene doesn't support it.

The report says evidence was concealed or destroyed, including video from surveillance cameras and parts of the records of the police central command center from the night of attacks. When the independent experts asked to see the fifth bus not included in the attorney general's investigation, they were led to one that didn't match the photographs or characteristics of the original.