An American man has been sentenced to more than 25 years in prison for leading a sex trafficking ring in Ecuador that was connected to the murder of a 15-year-old girl and the rape, sexual and physical abuse of dozens more.

Royce Phillips, 66, from Texas, and four Ecuadorean co-defendants, were jailed on Wednesday for 25 years and four months, the maximum sentence for people trafficking with the purpose of sexual exploitation.

Phillips, dubbed El Abuelo (“the grandfather”), ran the trafficking ring from his apartment in Quito Tenís, an upmarket neighbourhood in the Ecuadorean capital. Jonathan Paredes, Christian Álvarez, Carlos Erazo and Cristian Giler, who were convicted alongside him, groomed girls outside schools in the poorer district of Comité del Pueblo, in the north of Quito.

The girls were invited to parties, where they were plied with alcohol and drugs. Many of the 13- to 16-years-olds were secretly filmed for pornographic videos.

Last month, Giler, 21, was sentenced to 34 years and eight months for the rape and murder of 15-year-old Carolina Andrango in August 2018. She was beaten, raped and asphyxiated, and her body was dumped on a patch of waste ground.

The sentence was greeted with relief by the victims and their families, who had received harassment and death threats that forced at least one family to go into hiding and seek witness protection.

Phillips’ lawyers had called 191 witnesses, in an attempt to lengthen the trial, and successfully excluded the press and public from the hearings.

According to his Facebook profile, Phillips, from Corpus Christi, Texas, had lived in Quito for several years. His company has provided services to the oil industry and he counted important members of the country’s police and air force as friends. Photos on social media show him playing golf at the air force’s country club and posing with a squadron of police officers in uniform.

Phillips was arrested at his home in March 2019. At the apartment, officers seized sex toys, marijuana, party invitation flyers, a computer, two cameras, eight mobile phones, erectile-enhancement pills and thousands of dollars in cash, according to local media reports.

Gabriela* and her family were forced to leave Quito after she was threatened by Giler when she was 15.

“He [Giler] said if I ever said anything he would do worse things to me than he had done to La China [Carolina)]”, said Gabriela, now 18, who was a protected witness in the trafficking trial.

Her mother, Susana*, had found her daughter being assaulted by Giler, who managed to escape.

“She was so drugged, she was like a doll. She didn’t even know her name,” said Susana, whose daughter later begged her not to report him to the police.

Susana resigned from her job as a carer and took her two daughters to the coastal city of Guayaquil before relocating.

“In those days, they [the trafficking gang] were free, we had no one to protect us,” Gabriela told the Guardian.

Gabriela said she was flattered to be invited to caidas or parties at Phillips’ plush home. She said the Texan would stand in the doorway controlling who entered. Inside, alcohol and large quantities of marijuana were freely available. When the teenagers were intoxicated, Phillips would encourage them to have sex in two rooms equipped with hidden cameras.

“Giler and his gang would boast about the pornographic videos and the money they would make for each girl they brought [to Phillips’ parties],” she said. “They treated it like a joke.”

After the family received multiple death threats and were followed by suspicious vehicles, Ecuador’s interior minister María Paula Romo ordered police special forces to give the family round-the-clock protection.

Gabriela says while she is happy that “at last, they are in prison”, she still does not feel safe. She remains fearful that a hitman allegedly photographed with the gang at Phillips’ home is still at large and has been hired to kill her.

Lorena Grillo, a lawyer who advised Gabriela and her mother, said: “From a legal perspective, this sentence was the least one could expect from a case which has generated such uproar and alarm due to the appalling events which came to light.

“Regrettably, no matter how long the sentence is for this gang, there is always bitterness that the jail term, as it stands, is not long enough.”

* Names have been changed to protect the identity of certain individuals