An Auburn brother and sister and their two pals are accused of holding a New Jersey runaway hostage and brutalizing the teen with hair clippers, a machete and lit cigarettes in what one shaken cop likened to a “torture chamber.”

An emotional Auburn Officer George Vranos testified during a dangerousness hearing yesterday in Worcester District Court that the semi-finished basement room where the crime occurred looked like a “torture chamber, which looked like an interrogation room.”

The horrifying details of the 16-year-old victim’s ordeal, which stretched from Christmas Day to Dec. 27, was shocking enough for Judge Paul F. LoConto to order one of the four, Krystal Lugo, 23, held without bail until at least May 3. The others’ fates will be addressed tomorrow afternoon.

Lugo, mother to an 18-month-old daughter, her 19-year-old brother, Christopher Lugo, Krystal’s boyfriend, Yariel Torres-Abee, 22, of Southboro, and Yuleny Ortiz, 19, of Auburn, are facing kidnapping and assault charges. Christopher Lugo is also charged with rape.

Auburn Detective Vincent Ross testified the victim claimed Christopher Lugo told her she was drugged with marijuana laced with the sedative Xanax and sexually assaulted by multiple people Christmas Day after his sister and Torres-Abee picked her up in Leominster. It was not stated in court how they met.

Used condoms, an iron and pills were among the evidence Worcester assistant District Attorney Tara Nechev said were recovered at the Lugos’ White Terrace home after confidential informants alerted Auburn cops to the victim’s plight.

Nechev noted police have responded to the home 144 times since 2003.

Investigators have photos of two men they suspect are behind an armed home invasion at the house Dec. 27, which the victim was accused of setting up, police said.

Authorities reported finding evidence of gunfire in the kitchen.

Krystal Lugo “turned on the victim, blaming her for setting them up, for orchestrating the home invasion,” Nechev said.

“The victim was picked up by all of the defendants and put into the chair,” she said. “A machete was held at the victim’s neck at the direction of Krystal.”

Krystal Lugo, the victim said, also threatened to kill her and her family if she spoke to police.

Auburn Detective Eric Dyson testified about the moment he realized the victim’s tormenters had shaved her head, saying, “Her hair was in a Christmas bag.”