An image of Hector Figueroa taken from his Facebook profile. Figueroa counted Daniel Dion as one of his six friends on the social networking website. (Facebook)

The sister of Daniel Dion, a Canadian businessman killed last month in Mexico, is skeptical of the confession made by a suspect arrested in her brother's death.

Mexican police say Hector Figueroa, 46, a friend and former employee of Dion's, claims he punched the Canadian once, killing him. He then drove Dion's body to a remote location in Chilpancingo, 115 kilometres outside of Acapulco, and torched the car.

Sylvie Dion said she doesn't believe Figueroa. Speaking in French, she told CBC News it has been years since her 51-year-old brother had a drink. She also said Figueroa's claim Dion was killed by a single blow to the head was inconsistent with a pathologist's report.

Fernando Monreal Leyva, who is leading the investigation for the Guerrero state police, said charges have not yet been laid against Figueroa, and that the investigation is ongoing.

"The statement where [Figueroa] reveals these facts isn't enough," Leyva said in Spanish.

"We need proof to corroborate the confession that he made."

While Figueroa was serving a 15-year jail sentence for murder, he worked as one of 2,200 inmates Dion employed to make his line of eco-purses, police said. The two men met when Figueroa was released, and became friends.

Police had been looking for Figueroa to question him about Dion's death before he was arrested on Nov. 20.

Mexican police are now searching for Figueroa’s son, who has been missing since the investigation began into Dion's death.

Dion, who was originally from Sherbrooke, Que., but lived near Ottawa in the town of Carleton Place, had planned a month-long stay near Acapulco. He went missing on Oct. 23, and after a week of searching his body was found in the trunk of his burned out rental car on Oct. 30.

Mexican police have 20 days to compile evidence against Figueroa before formally charging him.