— The 20-year-old man charged with attacking his ex-girlfriend with a machete Thursday had stalked her following their break-up, a prosecutor said Friday.

Neel Salil Mehta, of 602 Halcyon Meadow Drive in Cary, is charged with assault with a deadly weapon with intent to kill inflicting serious injury, but Wake County Assistant District Attorney Anna Davis said authorities plan to upgrade that charge to attempted first-degree murder.

According to Apex police, Priyanka Kumari, 18, was walking home from a school bus stop Thursday afternoon when she was stabbed by Mehta outside a home at 1837 Venezia Way.

Davis said Kumari suffered wounds to her face, neck and hands and has already undergone at least one surgery at Duke University Hospital.

Pankaj Kumar said it's a miracle his daughter survived the attack and is already conscious and talking.

"There are so many cuts on the head," he said.

Witnesses said the assault lasted several minutes, and Davis said one person who called 911 said it appeared that Mehta was trying to decapitate Kumari.

"He's killing her," a woman told a 911 dispatcher, pleading for police and an ambulance to be sent to the scene quickly. "She's not going to make it. There's blood everywhere."

"You've got to get the cops here," a man told a 911 dispatcher. "I can't help here. It's like a big blade. He's going to kill her."

A man who lives in the neighborhood, who did not want to be identified, told WRAL News that he saw Mehta stabbing the teen repeatedly. He said he walked toward Mehta with a two-by-four – he didn't intervene out of fear for his own safety – but the threat of someone approaching with a board didn't stop the attack.

Police said that Mehta dropped the knife when officers ordered him to do so at gunpoint and took him into custody.

Mehta was taken by police to WakeMed with minor injuries that appeared to be self inflicted, police said.

Kumar said his wife called him to tell him of the attack on their daughter.

"She was not even able to speak, and I was speechless thinking of what might have happened," he said.

"When this person grabbed her from behind and the sides and started stabbing her, then she realized, this man is trying to kill me," he said. "She tried to stop using her hands, and then this guy grabbed her hand and then tried to chop it off."

Mehta told police that Kumari hadn't been returning Mehta's calls, texts or emails, and Davis said investigators determined that Mehta had been sending her threatening emails and had been planning the attack for about two weeks.

In searches of Mehta's home and cars, investigators seized a receipt from Carolina Partners, a mental health practice, along with a letter from an employment screening firm and a computer.

District Judge Margaret Eagles set Mehta's bond $2 million. If he is released on bond, she ordered that he remain under electronic monitoring and that he not have any direct or indirect contact with Kumari and her family.

"These kind of people should never come out (from behind) bars and be treated the same way," Kumar said. "He wanted my daughter to die. He should be brought to justice the same way."