Two longtime Colorado used car dealers face multiple charges – including sexual assault and human trafficking – in wake of a six-month investigation into a string of disturbing allegations that involved five victims.

Norman Boroumand, 45, was the owner of 1st Choice Motors in Greeley, Colorado, which has since been shut down. He and his alleged co-conspirator – Fares Al Rashed, the 38-year-old owner of Alrashed Auto Sales – are being held in the Weld County jail after they were indicted by a grand jury for several felonies.

Weld County District Attorney Michael Rourke says these are some of the worst allegations of sexual assault his office has ever heard. The defense, meanwhile, called it a "sham investigation" in court.

"Reading the information contained within the indictment and reading the information contained within the police reports is horrific," Rourke said. "It’s unbelievable that one or two individuals would do that to another human being."

One of the alleged crimes occurred as early as 2011, with another incident reported as recently as this year.

Prosecutors say in one case, Boroumand had hired a victim as an employee, and soon got involved in an intimate relationship with her – forcing her to have sex with him and Al Rashed, who investigators say gave the woman money.

She told police that she thought Boroumand would harm her if she didn’t comply.

According to the indictment, after a victim cut ties with Boroumand, he forced his way into her home by falsely claiming that his mother had a heart attack.

When she let him inside, she told police that he and Al Rashed dragged her to the bedroom and raped her.

Another time, when the victim went to Boroumand’s house to return her garage door opener and get her final paycheck, the indictment alleges he threw her cell phone at her and dragged her inside, where he sexually assaulted her.

Boroumand is also accused of throwing a victim’s phone at her and kicking her out of the house after he saw she received a text from another man. When she tried to come back to get her stuff, the indictment alleges that her pushed her down the stairs, injuring her.

On Jan. 1, the indictment alleges that a victim told police Boroumand went through her cell phone and punched her in the face after he became displeased with what he saw.

As the victim stood in the doorway and held her four-year-old daughter, the indictment alleges Boroumand pushed her to the ground.

She called police, but tried to recant her statement because she said Boroumand was her sole source of income.

Boroumand is also accused of threatening to harm a victim, going as far to tell her he would murder her in his basement and put her dead body in one of his vehicles – and then have it demolished.

The indictment also alleges that he sent a victim threatening text messages and left violent voicemails.

Boroumand is also accused of stalking a woman from June 30, 2014 until the present.

The indictment alleges he followed her, called and texted her, looked into her windows at night, and would hide in her home and attack her.

A victim told police that because of Boroumand’s stalking, she rarely left her house, received disability income from the state and could minimally function in her daily life.

Boroumand is also accused of calling a victim and harassing her – even as he was being held in the Weld County jail.

In wake of the indictment, Greeley Police arrested Boroumand Thursday night. Al Rashed was arrested early Friday morning.

Bond has been set for $3 million for Boroumand and $1.5 million for Al Rashed.

Rourke says the men have high bonds because they are "a risk to the public" and a "risk to the victims" -- as well as have the "ability to post very high bonds that many other defendants who come through out courtrooms don't have."

Boroumand has been indicted on charges of:

-Human trafficking for sexual servitude

-Two counts of criminal attempt to commit human trafficking for human servitude

-Two counts of second-degree kidnapping

-Four counts of sexual assault

-Possession of a controlled substance (anabolic steroids)

-Three counts of third-degree assault

-Seven counts of stalking

-Two counts of retaliation against a witness or victim

-Four counts of sexual assault

-Witness tampering

-Child abuse

-Domestic violence

Al Rashed has been indicted for:

-Human trafficking for sexual servitude

-Two counts of attempt to commit human trafficking for sexual servitude

-Three counts of sexual assault

Greeley Police believe there may be more victims. Anyone with information about the two suspects is asked to call Det. Elizabeth Finch at 970-350-9682, Det. Wendy Steward at 970-350-9692 and Det. Erin Gooch at 970-351-5352.

If you or someone you know has been a victim of domestic violence, you can reach the National Domestic Violence Hotline at 1-800-799-SAFE. Resources for victims are available at the Colorado Coalition Against Domestic Violence website:

"Acquaintance rape is no less serious of a crime than stranger rape," Rourke said, "and has the same if not more significant impacts on the victims."