JAKARTA, Indonesia -- A closed-door trial began Tuesday for the first of five janitors accused of raping a kindergartner in a bathroom at a prestigious international school in Indonesia that is facing a storm of controversy following more abuse allegations.

An American who taught at the Jakarta International School for 10 years killed himself earlier this year as the FBI was investigating evidence that he sexually abused scores of teen boys while working at 10 schools across four continents.

The custodians contracted to work at the school were arrested in April -- five men accused of attacking the boy and a woman accused as an accomplice. Police said one man committed suicide while in custody after drinking bathroom cleanser.

A media horde surrounded Agun Iskandar, 25, as he entered the courtroom. The remaining four suspects were expected to appear in court Wednesday, and the men could face up to 15 years in jail if found guilty. The 6-year-old boy's parents have sued the school, seeking $125 million in compensation.

All of the male defendants signed confessions, but one defence attorney, Mada Mardanus, argued they did so only because they were being tortured by police. He said the suspects deny the accusations.

Jakarta police spokesman Col. Rikwanto, who uses one name, strongly denied that any of the suspects were tortured during police questioning.

Mardanus also said the evidence was weak, with medical reports finding the boy had no major injuries or abnormalities even though the prosecutor's indictment alleged he had been sodomized up to 13 times.

"We don't want the court to punish the innocent simply because of public opinion, or just to please the public," Mardanus said. "We hope the judge can see this case fairly, proportionately and humanely."

The family's lawyer, Andi M. Asrun, questioned the defence attorney's claim. "How could they know the results of the medical reports, which are concealed and only for investigation purposes?" he said.

The American teacher, William Vahey, taught at the Jakarta school from 1992 to 2002, though no allegations have been made that he abused students there. The FBI says the teacher who had a four-decade, international career may have molested scores of boys after giving them sleeping pills. He killed himself in Minnesota in March.

Since the custodians' case surfaced, two other families of young male students have come forward, and two school staff members have been detained without charges.

A campaign on social media has called for the release of Canadian school administrator Neil Bantleman and Indonesia teaching assistant Ferdinant Tjiong, who were arrested in July and are not part of this trial. Both have denied the allegations.

"We have zero doubt in the allegations against those teachers -- that the allegations are false and they are innocent -- and we are confident in the justice system that with time, they will be let free," said Steve Druggan, deputy head of school for learning.

The school is attended by the children of foreign diplomats, businesspeople and Indonesia's elite. It has 2,400 students aged 3 to 18 from about 60 different countries.