Mom of Indiana woman accused of kidnapping and suffocating her son and daughter to death says she's 'evil' and her children were scared of her.

The mother of an Indiana woman accused of kidnapping her two young children and then driving to a police station with their lifeless bodies in a car trunk described her daughter as 'evil' and said she was a bad parent.

Amber Pasztor, 29, has been charged with two preliminary counts of murder in the deaths of her daughter Liliana Hernandez, seven, and six-year-old son Rene Pasztor. 

An Amber Alert had been issued for the children in Fort Wayne Monday, saying they were 'believed to be in extreme danger.'

Five hours later, the brother and sister were found dead 70 miles away in Elkhart, Indiana, inside a car belonging to Pastorz's neighbor who was shot to death.

An autopsy Tuesday determined Liliana and Rene died of asphyxiation, Elkhart police Sgt. Chris Snyder said. 

Amber Pasztor, 29 (pictured), was arrested on Monday and charged with murdering her six-year-old son Rene Pasztor and her seven-year-old daughter Liliana Hernandez.

Amber Pasztor, 29, was arrested on Monday and charged with murdering her six-year-old son Rene Pasztor (left) and her seven-year-old daughter Liliana Hernandez (right).

Speaking to People Magazine Tuesday, Amber Pasztor's mother, Leanna Pastorz, said she was not surprised to learn of the charges against her daughter, whom she labeled 'evil.'

'We thought she was crazy,' Leanne Pasztor said of her 29-year-old daughter, who had lost custody of her two children more than a year ago due to drug addiction. 'I think her thought was, "If she can't have them, nobody can."' 

Liliana and Rene, who according to their grandmother were scared of their mother, moved in with another relative, Emily Lasko Green, and were apparently happy in their new home.

Green told the website that she had gone through 'hell' to gain custody of the brother and sister, whom she described as 'wonderful.' 

'They were our babies,' Green said. 'God gave us babies and she took them away.' 

Elkhart County Prosecutor Curtis Hill said at a news conference Tuesday afternoon that he expected to formally charge Amber Pasztor in the deaths of the children later this week.

'It's a senseless tragedy,' Hill said. 

Pastorz was due in court for a probable cause hearing Wednesday afternoon. 

The body of 65-year-old Frank Macomber was found early Tuesday morning by an FBI agent searching the area near the home where the two children were abducted.

Macomber's daughter says he was neighbors with Pasztor, who used to make him drive her around. When his photo was released in the Amber Alert on Monday, his daughter feared that he was being used against his will.

A prosecutor said Macomber probably died before the children were abducted.

After Pasztor's arrest, police continued to search for Macomber. They tried his home, but had no luck, and then focused on the area around the home where the kids' were abducted.