A Minnesota woman charged with shooting her boyfriend of five years has told police it was due to a YouTube stunt gone horribly wrong.

Monalisa Perez, 19, of Halsted, allegedly shot Pedro Ruiz III, 22, in the chest with a .50-caliber Desert Eagle pistol on Monday while their three-year-old daughter looked on.

Perez fled the house screaming and later said the book was supposed to stop the bullet in a bid to create a viral video, family members told the Star Tribune.

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Monalisa Perez (pictured), 19, of Halsted, allegedly shot Pedro Ruiz III, 22, in the chest with a .50-caliber Desert Eagle pistol

A Minnesota woman charged with shooting Pedro Ruiz III (pictured), her boyfriend of five years, has told police it was due to a YouTube stunt gone horribly wrong

Perez posted this tweet the day of the shooting. His family said he was supposed to stop a .50-caliber round with a book held in front of his chest. Instead it killed him

Perez (left) fled the house screaming and later said the book was supposed to stop the bullet in a bid to create a viral video

Prior to the shooting, Perez had tweeted: 'Me and Pedro are probably going to shoot one of the most dangerous videos ever. HIS idea not MINE'.

They had planned for Perez to fire the large-caliber handgun at a hardcover encyclopedia being held by Ruiz outside their home on HWY 75, around 6:30pm.

Perez told police that she had fired the fatal shot while stood just a foot away from Ruiz, according to the prosecutor.

She claimed the plan was Ruiz's own, and that he had showed her another book that had successfully stopped the bullet.

This time, however, it penetrated the volume and killed him. His death was captured on two cameras that had been set up to record the stunt; police say they do not plan to release it at this time.

Perez then called 911; EMTs attempted chest compressions on Ruiz, but were unable to save the young man.

Their three-year-old daughter, Aaliyah, was reportedly present when the shooting occurred.

Perez, who is pregnant with the couple's second child, has been charged with second-degree manslaughter.

'Prankster': Monalisa Perez allegedly shot her boyfriend of five years on Monday while filming a YouTube 'prank', his family said. Perez (left in mugshot, and right with Ruiz) has been arrested

Witness: The couple's daughter, Aaliyah (pictured with Perez) was witness to the shooting, police said. The girl was a regular fixture in the couple's videos

Perez told police that she had fired the fatal shot while stood just a foot away from Ruiz (pictured), according to the prosecutor

The Desert Eagle is described as 'one of the world's most powerful semiautomatic handguns' by online retailer Cabelas.

A video by an unrelated YouTuber, 'Tom Bulletsafe' shows a .50 caliber Desert Eagle firing straight through 24 sheets of drywall.

The victim's aunt, Claudia Ruiz, told WDAY-TV that she told her nephew: 'Don't do it. Don't do it. Why are you going to use a gun? Why?'

She said he replied: 'Because we want more viewers. We want to get famous.'

The couple's YouTube channel, which includes pranks such as Perez feeding Ruiz donuts covered in baby powder, typically received between 400 and 900 views per video, and had 218 subscribers.

In their last video, the family go to a fairground and Perez remarks: 'Imagine when we have 300,000 subscribers.'

'I told them, the bigger we get, I’ll be throwing parties,' Ruiz replies.

'They were in love. It was just a prank gone wrong. It shouldn't have happened like this. It shouldn't have happened at all,' Claudia Ruiz told the West Central Tribune.

'I wish they wouldn't have done it. I wish he would've just done another prank.'

Celebrity: The couple hoped that the stunt would make them YouTube celebrities. Perez reportedly told police she had fired the bullet from a foot away

Gun: Ruiz was shot with a highly powerful .50 caliber Desert Eagle (pictured along with several .50-caliber bullets in file photo). He was described as a 'daredevil' by family

Another of Ruiz's aunts, Lisa Primeau, said she 'pretty much raised Ruiz' after his mom died when he was nine and living with his dad hadn't worked out.

She told the Star Tribune that Ruiz was a gun enthusiast and 'daredevil' who was always 'putting a dangerous twist on everything he did.'

That included 'jumping into the swimming pool from the top of the house, no hesitation,' she said, and being 'a crazy driver with go-carts.'

Neighbor Wayne Cameron and around 30 others watched the paramedics' failed attempt to save Ruiz before he was airlifted to a Fargo hospital.

'Everyone was crying. I just couldn't take it anymore so I had to go back home,' he said.

The couple have uploaded a string of YouTube videos centering on their lives with Aaliyah.

In some of them Perez 'pranks' a sleeping Ruiz; in one she pours hot candle wax onto his back while he's asleep, jokingly asking him if he thinks it's sexy.

In another she feeds her sleepy boyfriends a donut covered in baby powder.

Pregnant: Perez is pregnant, and is expecting to give birth in September. In May the couple revealed the child's gender in a YouTube video

Family: Perez had Aaliyah when she was 15, and is expecting a baby boy in September. Ruiz had been training to be a foreman in order to provide for his growing family

Plans: Perez said on Facebook shortly before Ruiz died that she had been planning to make a YouTube account specifically for him to post 'crazy stuff'

Several of their videos focus on them playing with their daughter, taking her to the countryside and having pillow fights in their living room.

In May, they announced on YouTube that their second child would be a boy; he is due in September. She had Aaliyah when she was 15.

In Facebook comments made shortly before Ruiz's death, Perez said: 'We are in the process of making Pedro a YouTube channel oh man is it going to be sweet! LOL.'

She added: 'All the crazy stuff will on his channel and mine will be our family life!!!'

Primeau said that Ruiz, an employee of BNSF Railway, had been training to become a foreman in order to support his growing family.

She added that she and his other relatives 'are all supporting Mona. It's a tragic incident.

'What she did ... she has to live with that. It's the worst punishment she can get. She is pregnant with their second kid. It's just heartbreaking.'

If convicted, Perez could face a maximum of ten years in prison, or a fine of $20,000, or both. She remains in regional jail in Crookston.