Teen Killed Parents, Then Lit Candles and Commented on Their 'F--king Rotten' Bodies on Video: Docs

On Thursday, the Waukesha County Sheriff's Department announced new charges for Nikita Casap, a 17-year-old teen previously arrested and charged with felony counts of operating a motor vehicle without the owner's consent and theft of movable property after his mother Tatiana Casap and stepfather Donald Mayer were found dead in their Village of Waukesha home on February 28.

The additional charges include 2 Counts of 1st Degree Intentional Homicide, 2 Counts of Hiding a Corpse, Theft of Property Over $10,000 and 2 Counts of Misappropriating ID to Obtain Money. Per FOX 6, the auto theft charges were dropped, while his bail was set for $1 million.

A criminal complaint filed on Wednesday also provided new details about the investigation into Casap, detailing the crime scene, security footage discovered at the time of his arrest and interviews with witnesses.

Per the docs, via Law & Crime, authorities were called to the family's home on February 28 for a welfare check, after Mayer's mother called to report she hadn't heard from her son in weeks. The mother also allegedly contacted the teen's school and was told he had been MIA for two weeks. The school told authorities he stopped coming in starting February 12, with an email sent to them claiming Casap was sick. It's unclear who sent the message.

Mayer's employer claimed he had been in contact with the victim via text between February 13 and 25th, with the messages indicating Mayer was sick and would not be back to work until March 3. The manager said the messages were "uncharacteristic," leaving him "concerned for his health and well-being."

When authorities entered the home for the welfare check, deputies "immediately smelled an odor of decay" -- before spotting "a blanket covering something in the hallway." That something, said authorities, was Tatiana Casap, whose body was surrounded by "dried blood" and face was "blackened with decomposition." A "possible bullet hole" was also spotted in the wall nearby.

Authorities then obtained a search warrant for the home, before later finding Mayer's body "covered by blankets and pillows" in the first floor office.

The teen, however, was nowhere to be found -- so he was marked as missing, while the Mayer's Volkswagen Atlas, which was also MIA, was reported as stolen. Also not found in the house were Mayer's Smith & Wesson .357 Magnum and the family dog.

Authorities described what sounds like a chaotic scene inside the home, with artwork removed from the walls, open drawers everywhere and items "thrown to the floor." The docs note law enforcement believe someone was searching for "money hidden in various locations" throughout the home.

As authorities pinged the cell phones of both victims and the teen, they traced the latter to a truck stop, where footage showed someone matching Casap's description with his stepfather's vehicle and the family dog. A traffic stop was later performed on the same car on February 28 in Kansas, with Casap driving and both the dog and Mayer's gun found inside the vehicle.

Neighbors told authorities they last saw Mayer on February 9 or 10th, adding they thought it was "unusual" when he didn't put their garbage out for weekly pickup on February 13.

A medical examiner later estimated the date of death being February 11.

Per the docs, the ME said a visual confirmation on the two victims wasn't possible "based upon the state of decomposition" for both bodies. Mayer was found to have what is believed to be a bullet wound in the back of his head, while his wife's body had four sets of "possible entrance and exit wounds" found on the neck, torso, abdomen and right wrist.

The cause of death for Mayer was deemed a gunshot wound to the head, while Casap died from multiple gunshot wounds. The manner of death for both was listed as homicide.

Bullet fragments in the bodies matched those found in Mayer's vehicle when the teen was apprehended.

The docs claim deputies later did a full search of Mayer's vehicle, in which they found credit cards in the names of both victims, jewelry, a "pried-open safe," passports, $14,000 in cash and a surveillance video camera.

The surveillance camera still had its memory card inside, and the footage showed the suspect's actions in the home after his parents were killed.

Per the complaint, the video showed Casap "entering the room to keep candles lit near [Mayer's] deceased body." At one point, he was also allegedly seen "holding a phone in his right hand as if taking a picture" near the body, before grabbing the camera, turning it around to face a chair, before someone -- presumably the suspect, per authorities -- is heard saying, "So, you can see him there. I can literally see the f--king rotten body there."

Mayer's brother allegedly told authorities he did have contact with the victim on February 14 -- but, in retrospect, believes his "responses were somewhat unusual for him." Mayer's boss, meanwhile, is also quoted as saying texts he received from him between February 13 and 25th "did not sound like" they were coming from the victim.

Video from February 11, meanwhile, showed the teen's then-alive mother wearing the same clothes she was wearing when her body was found 17 days later.

An interview with a classmate of Casap's from Waukesha West High School was also detailed in the complaint. She claimed the suspect had been sending her "gory" war videos set to Russian music, gave her a "detailed description of how he wanted to kill himself" and said he "was planning to kill his parents and them himself so they would do not have to live without him."

Per the docs, she said she told him to seek help, while he allegedly threatened her -- saying, "If anyone found out what he told her, that something bad was going to happen to her or in his words, 'It wouldn't end well' for her."

The classmate further told detectives, according the complaint, that Casap told her he was talking to a man in Russia. Investigators looking at Casap's phone, meanwhile, did find messages to someone who responded in Russian. According to Law&Crime, Casap and his mother are from Moldova, which sits just below Ukraine.

In one message, per the docs, Casap allegedly wrote, "How long will I need to hide before I will be moved to Ukraine? Also I probably should brush up on my Russian, because I can understand just fine but speaking is harder lol."

In another message, he allegedly added, "So while in Ukraine, I'll be able to live a normal life? Even if when it's found out I did it?" -- while, in yet another text, he wrote about needing headphones "to protect hearing gunshots of a .357 Magnum."

Per FOX 6, he'll be back in court for a preliminary hearing on April 9.