KUALA LUMPUR, Malaysia - A Malaysian opposition aide may have been strangled and beaten before falling to his death from anti-corruption offices where he was being questioned, a renowned Thai pathologist said Wednesday.

Porntip Rojanasunan, head of Thailand's Central Institute of Forensic Science, was a star witness at the inquest into the aide Teoh Beng Hock's death, which has caused a political storm in Malaysia.

The flamboyant expert, well known for challenging authorities in her home country, said there was an 80 percent chance that 30-year-old Teoh was murdered and just a 20 percent chance of suicide.

In a report submitted to the inquest, Porntip said there was evidence that Teoh had sustained serious injuries before he plunged from the 14th floor of the Malaysian Anti-Corruption Commission (MACC).

His crumpled body was found on July 16 on the roof of an adjacent building after he had undergone questioning until 3.45 am as part of a probe into the opposition-held Selangor state government.

Porntip, who has not inspected Teoh's remains, said there was evidence of injuries not consistent with a fall, including a skull fracture and a tear to his anus which was "more of a penetrating injury".

"I cannot exclude manual strangulation on the neck," she added.

The Thai expert's analysis was based on a study of two government forensic reports. She challenged their conclusion that Teoh was conscious while falling.

The anti-corruption body says that after being discharged, Teoh chose to rest in the building and was seen just before dawn the same day sleeping on a sofa, but was not seen again until his body was discovered that afternoon.