In one message last week, she apparently hinted at their February 14 plan, writing: 'It's almost here. The clock is ticking'

According to Facebook, her father is from Laos

Souvannarath posted graphic images of the Columbine murders and Hitler to Facebook and Tumblr, and gave her support to white supremacists

The 23-year-old American woman who allegedly plotted to carry out a massacre at a Canadian mall on Valentine's Day posted harrowing messages online for years before the plan was foiled.

Lindsay Kantha Souvannarath, from Geneva, Illinois, posted about her admiration of Hitler, the Columbine killers and other murderers on her Facebook page, Tumblr site and forums, and even hinted at the deadly plan, writing last Wednesday: 'Valentine's Day. It's going down.'

Two days after the post, she was arrested and charged with conspiracy to commit murder after police received a tip. Randall Shepherd, 20, of Nova Scotia was arrested on the same charges.

A third suspect, James Gamble, 19 killed himself as police moved to arrest him at his home in Nova Scotia, and a fourth - a 17-year-old boy - has been released from custody.

Angelic? Lindsay Kantha Souvannarath, pictured left in her high school yearbook photo and right in a recent Facebook photo, was arrested after landing in Canada, where she allegedly planned to execute a massacre

Online profiles show the named suspects had been exchanging unnerving messages for years.

The dark messages come in stark contrast to Souvannarath's high school yearbook photo shared by the Kane County Chronicle, which shows a pretty teen. She went on to study at Coe College, where she studied English and creative writing before graduating last year.

But online, Souvannarath, whose father is from Laos, painted herself as a neo-Nazi and regularly shared photos of Hitler while lauding white separatists, such as former Ku Klux Klan leader David Duke.

'Free speech is dead,' she apparently wrote in one forum in 2007, when she would have been just 15. 'That's why we need people like David Duke to bring it to life again.'

Her Tumblr account is entitled 'c**kswastika', according to the Chronicle Herald.

On the page, she displays a large pink swastika and links to James Gamble's Tumblr page, which shows images of Hitler, dead bodies and murders, and videos of the Columbine shooters.

Gamble's page also features conversations that include graphic sexual descriptions as well as naked images of himself.

Ominous: Last week, she posted this message showing 'Saturday the 14th' - the day of the alleged massacre - in bloody, dripping letters with the message: 'HA HAHA' posted beneath

Terrifying: She also shared this image with the words 'Valentine's Day. It's going down' with the names 'C***swastika' and 'Shallow-Existences', which refer to her and James Gamble, another suspect

Harrowing: Beneath the poster, she apparently added this chilling message on her Tumblr page

'I'm such a morbid f***ing freak,' he writes in one post. 'I love it.'

Her Tumblr page also features images of the Columbine shooters, Eric Harris and Dylan Klebold, including photos of their dead bodies,

'Eric and Dylan are dead, but Reb and VoDKa live,' she wrote, apparently referring to Gamble.

In one post from February 11, she shared a movie poster showing two ghoulish figures with the words: 'Valentine's Day. It's going down' - perhaps hinting at their alleged plan for February 14.

Beneath the poster she added: 'It's almost here. The clock is ticking.'

She also shared quotes from murderers and photos of weapons. One picture shows a man holding a gun and wearing a t-shirt that reads: 'Natural selection.'

Another post on her blog reads 'Saturday the 14th' in red, dripping letters with the comment: 'Ha Haa' written beneath.

Her website is still showing new updates. Police said that she had pre-programmed online messages before she was due to carry out the attacks and ultimately kill herself.

'Shooting obsessed': Randall Shepherd, 20 (left), and James Gamble, 19 (right), allegedly plotted the mass shooting with Souvannarath. Shepherd has now been charged but Gamble killed himself before his arrest

Sick: A Tumblr page that appeared to belong to Gamble shows his obsession with the Columbine killers (Dylan Klebold is pictured center) as well as crime scenes, Nazis, guns and torture

Shepherd has his own Tumblr page with the name genesistogenocide, according to the Chronicle Herald. The page is an ode to 'gore, porn, Columbine, horror and heavy f***ing metal'.

Again it features images of mass murderers, the Nazis and pornography.

As well as posting to Tumblr, Souvannarath and Shepheard appear to have been active on the online chat board Random Insanity, according to the Chronicle Herald. She appears to go by the name SnoopyFemme.

They are also connected with each other and Gamble on Facebook, where Souvannarath again shares violent images and her own Nazi-themed sketches.

The group, labeled by police as 'murderous misfits', had conspired to carry out a mall massacre on Valentine's Day and then take their own lives, authorities said.

Investigators say the group planned to open fire inside Halifax Shopping Centre on Saturday.

The plot was foiled by law enforcement at the last minute after they received a tip-off from a member of the public, according to a Halifax Police statement.

'Based on what we know so far, it would have been devastating - mass casualties would have been a real possibility,' Justice Minister Peter MacKay told reporters on Saturday.

Chilling: She shared these selfies to Facebook, including one wearing a skull mask, right, like in the poster

Terrifying: A user that appears to be Souvannarath posted numerous messages to forums, including this one commending former Ku Klux Klan leader and neo-Nazi David Duke

Chilling: In 2013, she uploaded this sketch she made, including Nazi emblems and the phrase: 'White Power'

'The attack does not appear to have been culturally motivated, therefore not linked to terrorism.

'A day known to represent love and affection could have taken a much different meaning today had it not been for the exceptional efforts of the combined law enforcement community.'

Souvannarath was arrested arriving at Halifax Stanfield International Airport by the Royal Canadian Mounted Police airport at 2am Friday. where she was being picked up by Shepherd.

A senior police official told The Associated Press that Souvannarath confessed to the plot after her arrest. She had also programmed a number of tweets to be posted posthumously, the official said.

On Saturday, the young woman's family posted a note to their door in Illinois reading: 'We are very sorry, but we are not prepared to make a statement at this time.'

A neighbor, Kathy Schooley, told the Chicago Sun Times that she hadn't seen Souvannarath in a while but remembered her as a 'normal girl' who often changed her look from Goth to girly.

Police said the group had access to firearms and presented a significant weapons-related threat. Weapons were seized by investigators, but it is unclear what type.

Gamble was found dead inside his parents' home in Timberlea at 1.20am on Friday, after officers surrounded the property. Police heard a single gunshot before entering the house.

Plot: Canadian police have foiled a murderous plot that would have seen at least two people storm a public place and kill as many people as possible on Valentine's Day before committing suicide, officials have said.

Scene: Gamble, 19, killed himself at this Timberlea house early Friday after police surrounded the property

Target: Police say they have confirmed the target for the massacre was to be the Halifax Shopping Centre

Gamble's father told local media he needed privacy to grieve the death of his son, according to Global News

The fourth suspect, a 17-year-old boy, who was arrested at 11am Friday at a house in Cole Harbor, has now been released by police without charge but remains under investigation.

The plot was intercepted after a tip off by a member of the public.

According to CBC, the information came from Geneva, where Souvannarath lives.

The tip only came in on Thursday and police were able to make the arrests within a matter of hours.

Police said the four alleged plotters 'had some beliefs and were willing to carry out violent acts against citizens'.

On Friday, Mike Savage, mayor of Halifax, applauded the work of police in Canada, describing the arrests as 'a great example of the fine work they do on a daily basis to help keep Canadians safe.'