Former world boxing champion Arturo Gatti, whose body was found in a Brazilian apartment earlier this month, learned to box in Montreal and moved to New Jersey to pursue the sport professionally. (Richard Drew/Associated Press)

Brazilian police have concluded that former world boxing champion Arturo Gatti committed suicide and ordered that his wife be released.

Lead investigator Paulo Alberes told The Associated Press that Gatti, 37, killed himself on July 11 in a seaside resort in northeastern Brazil. He offered few other details but said he would hold a news conference later Thursday.

Gatti was born in Italy but grew up in Montreal, where he was buried July 20.

Police had detained his wife, Amanda Rodrigues, 23, accusing her of strangling Gatti with her purse strap as he slept after getting drunk.

On Thursday, state court Judge Ildete Verissimo de Lima in the city of Recife ordered that Rodrigues be immediately released. Her lawyer, Celio Avelino, said Rodrigues would walk out of jail Thursday afternoon.

"The victim ... committed suicide by hanging," Lima's ruling read, referring to the findings of a police investigation.

Gatti was found dead in a northeastern Brazil apartment he was renting with his wife and their 10-month-old son.

A Brazilian newspaper had earlier reported that an autopsy revealed Gatti may have committed suicide because his body was found hanging. But the report also allegedly said that he could have been murdered or that his death may have been an accident.

Family rejected suicide rumours

Gatti's friends and family have strongly rejected any suggestion that he may have taken his own life. Family friend Ivano Scarpa told CBC News Gatti had no reason to consider suicide.

"You know, there's absolutely nothing that could have [caused] him to be depressed," Scarpa said. "No financial problems, no women problems per se — sure he was married to Amanda, but if [it] didn't work out with her, there [were] two dozen women waiting in line."

After learning to box in Montreal, Gatti followed his older brother, Joe, to New Jersey to pursue a professional boxing career.

He started his pro career in 1991. He won two title belts, in two different weight classes, in a 16-year career that lasted until 2007, after which he moved back to Montreal. He finished with a record of 40-9, with 31 knockouts.

He won his first world title, the WBC championship as a junior welterweight, by beating Tracy Harris Patterson, in 1995 in Atlantic City. In 2004, he won the WBC super-lightweight title, also in Atlantic City.

With files from The Associated Press