Pictured in her mugshot is the 16-year-old girl accused of stabbing her Uber driver to death with a knife and a machete she stole from Walmart in a crazed early morning attack.

Eliza Wasni was ordered held without bail at her first hearing in Cook County, Illinois court on Wednesday.

The teen, who lives with a single mother in Norwood Park, stands accused of murdering Uber driver Grand Nelson, 34, after getting a ride from him early Tuesday morning.

Wasni kept her head on the ground for most of the court appearance, as she was charged as an adult with first-degree murder. She only spoke up once, to confirm her name. She is currently being represented by a public defender, and will be jailed at a juvenile facility.

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Eliza Wasni, 16 (pictured), has been charged as an adult with first-degree murder in the death of Uber driver Grant Nelson

Nelson (right) was driving Wasni (left) early Tuesday morning when she attacked him with two knives she stole from Walmart, prosecutors said

Nelson fled his vehicle (above) and tried to get help, but later died at the hospital

Prosecutors called the crime 'heinous' and Judge Michael Hood agreed that Nelson's murder was 'extremely violent'.

Nelsons parents as well as his two siblings, Todd and Alexandra, were in the courtroom during Wednesday's hearing.

Family members could be heard sobbing at times as prosecutors read out a two-page description of the murder.

The description offers no reason for the attack, but portrays Wasni as a calm girl who 'nonchalantly' could be seen walking through Walmart earlier in the evening, with a knife and a machete in hand, before she walked outside without paying.

Prosecutors said that Nelson, a resident of Wilmette, picked the girl up shortly after 3am Tuesday in Lincolnwood. It was her third ride in an Uber vehicle in the early hours of Tuesday.

It's unclear what prompted the attack. Prosecutors say Wasni stole the car but abandoned it soon after striking a median

Nelson ran into this condo and tried to get help from residents, yelling 'Help me, help me! I'm going to die!'

Two minutes after he began driving, prosecutors said that Wasni began stabbing Nelson from the back seat. Nelson was able to pull over and ran into a nearby condominium building, where he screamed, 'Help me, help me! I'm going to die!' until residents called 911.

Wasni climbed into the front seat of Nelson's blood-splattered silver sedan and drove away, striking a median in the road. She jumped out of the vehicle and fled on foot.

When Lincolnwood police arrived, they found the vehicle with blood on both the inside and the outside, with Nelson's phone open to the Uber app. The app said that Nelson's passenger was someone named Eliza.

Officers followed the trial of blood and found Nelson lying in grass. He was bleeding profusely from several wounds, and was able to tell the officers what had happened. He died at a nearby hospital a few hours later.

Todd Nelson said that his brother Grant (pictured) was 'the most gentle, kind person. He never hurt anyone. He was good to animals, he was good to children'

Nelson is pictured on the far left with members of his family in a photo shared to Facebook. The family attended Wasni's first hearing on Wednesday

Using the description given by Nelson, police found her nearby crouching behind an air conditioner - a machete in one hand and a knife in the other. Police warned her that she would be shot with a Taser if she did not drop the weapons, and when she did not comply an officer used the Taser. Wasni dropped the knives and was taken into custody. Police said she did not make a statement.

According to prosecutors, police recovered a shirt the girl could be seen wearing in the Walmart. The shirt had blood on it.

Uber officials said the company was working with police to provide information relevant to the investigation.

'We are heartbroken by the loss of one of our partners,' Uber said in a statement. 'Our deepest sympathies and prayers are with his family and loved ones during this incredibly difficult time.'

They also said that she appeared to be in violation of the company's rules, which states that riders must be 18 years or older.

The company spokesman said that a rider's access can be removed if they are found to be underage, and that there is a mechanism as well for drivers to report riders they suspect of being underage.

Nelson's sister told WMAQ-TV in Chicago that her brother was a good person.

'He was not a vindictive person,' Alex Nelson said. 'He was not a cruel person. He didn't deserve this fate.'

She added to the Chicago Tribune that she hopes 'justice will happen' in the 'horrifying and maddening murder'.

Brother Todd Nelson said that his bother was 'the most gentle, kind person. He never hurt anyone. He was good to animals, he was good to children'.

Nelson lived at home with their parents and worked as a waiter. He drove for Uber and Lyft after his shifts to make money.

'He was just trying to do the best he could in life,' Todd said.

Friends told ABC7 that Nelson was driving that night because he could get higher fares for the holiday.

'It was surging. He said it's just opportunity to make some more money,' a friend, Waqas Abbasi said.

It is the first homicide in Lincolnwood since 2006, police said.