It is understood the twins' South African-born parents live in Surrey Hills, Melbourne, and the twins attended the nearby exclusive Methodist Ladies' College before they both graduated with double degrees from university. An image from the Family Shooting Center website. The twins' mother and father, believed to be a former banking executive, are en route to Denver to be with their surviving daughter. According to a court document obtained by a US news site, the sisters had been sharing a hotel room in La Quinta Inn on Arapahoe Road, Denver, before their ill-fated trip to the Family Shooting Range on Monday afternoon, US time. The reported court document provides a chilling description of what police found when they arrived at the gun range after the sisters were shot.

One of the women was on her back while a shooting range employee desperately performed chest compressions on her, the document reportedly records. The woman was pronounced dead at the scene. Where the shootings happened. Her sister was sitting nearby with a gunshot wound in the centre of her forehead, the document reportedly says. She was taken to Colorado's Swedish Medical Centre in a critical condition and has since undergone several operations. The Victorian twins had their hair "done fancy" and seemed "pretty happy" when they arrived at the Family Shooting Centre in Colorado before the mysterious incident. Credit:Getty, AFP

Police searched their room after the shooting and found shopping bags, purses, backpacks, duffel bags, and suitcases. Inside the bags were clothes, blankets, jewellery, mobile phones and money. The shooting range's sign. She was devastated, frustrated, distraught and angry at times. Her emotions ran the entire gamut. I think any of us in that situation would run the same gamut of emotion By this morning the survivor's condition had improved enough for her to speak to police for the first time, telling them from her hospital bed that she entered into a suicide pact with her sister.

But during the two-hour interview, she refused to say why they hatched the plan. A spokeswoman for Methodist Ladies College in Kew today said she could not comment on whether the women were former students until their names had been formally released. The shooting range, located at the Cherry Creek State Park, has declined to comment further on the incident. Sheriff's statement Captain Louie Perea of the Arapahoe County Sheriff's Office said in a statement that "the surviving sister ... has confirmed that they had planned to commit suicide together, and did in fact shoot themselves".

"Based on the physical evidence collected, the surviving sister's statements, and video surveillance footage from the shooting centre [which will not be released], the Arapahoe County Sheriff's Office believes that this incident was indeed a suicide and attempted suicide." But he said the twin did not want to say why they came up with such a plan. "We asked that question, obviously more than once, and she didn't want to answer that question. "We do not know why they did it. "But, we do know they were in the Denver area for five weeks and one of them went to the shooting range approximately two weeks ago and took some shooting lessons and then about a week ago they went to the same shooting range and took some more lessons.

"Obviously they went back to the shooting range on November 15 [Monday] and shot themselves." The twins' parents will arrive in the United States tomorrow, the twins' second cousin, who lives in the US, said. Their names will not be released until police formally identify them from fingerprints taken by immigration officials when they entered the country. 'Highly emotional state' Captain Perea said the twin was highly emotional and "devastated, frustrated, distraught and angry at times".

"Her emotions ran the entire gamut. I think any of us in that situation would run the same gamut of emotion." The cousin, Jacqueline Sole, of Washington, said yesterday she did not know them well but was shocked. "They were smart, had degrees and were well travelled," she said. "Maybe in the coming days more light will be shed on this senseless tragedy." She wrote on The Denver Post's website that her family were praying for the recovery of the surviving twin. "I am not by any means an official spokesperson for the family, but from what I am told the twins' parents will be arriving sometime Saturday to try and help make sense of this awful tragedy," she wrote.

"I don't think any of us can begin to speculate what caused my cousins to act so irrationally." Ms Sole told the Post the shootings had hit the family hard. "I feel so helpless. These are such young lives." Shot with separate bullets from separate guns Police had been unsure what happened in the moments before the shooting. But last night they determined the women were shot with separate bullets from separate guns, that no third party was involved and that they had fallen to the ground almost simultaneously.

Ms Sole wrote that the family was "all grieving the senseless death of the one whilst praying for the recovery of the other". "I ask that you keep their parents in your thoughts and prayers as they try to come to grips with what has happened." The cousin said she wished the twins had contacted her if they had problems. "Totally senseless, wish they could have figured out a different way to deal with whatever was plaguing them," she wrote. "Wish they knew where I was, so near, I would have helped. RIP my young cousin."

Sisters 'didn't lack for anything' Ms Sole told the Post the cousins were born in Melbourne after their parents migrated to Australia from South Africa in the 1970s. They "grew up in a loving home" in a middle-class family and "didn't lack for anything", she said, adding that they looked "remarkably alike", were not married and did not have siblings. Both the sisters graduated with double degrees in Australia and made several trips to the US and Canada, sometimes separately. They worked in the United States, with one twin employed as a nanny. ""They kept to themselves when they were able to travel. Once in a blue moon they would email their mum and say: 'We're OK.'"

One twin was more outgoing while the other was quiet and reserved, Ms Sole said. She said she did not know the twins were visiting Denver. "I guess they just got a bee in their bonnet and that's where they went." Captain Perea would not confirm what the women were doing in the US and said the authorities' decision to not reveal their names meant police had been unable to speak to friends or associates. An employee at the ranch yesterday said that the girls, who arrived in the US in August and September on cultural exchange visas, wore make-up and had their hair "done fancy" when they arrived at the range.

They seemed "pretty happy and normal, they didn't seem stressed out" as they shot targets in different stalls for about 90 minutes before the tragedy. The range, within the grounds of a large state park, offers separate locations for pistol, rifle and skeet shooting. The rifle range adjoins the smaller pistol range. Police have recovered their personal effects, from the La Quinta Inn and Suites, a beige and featureless building on Colorado's main north-south traffic artery, in the southern Denver suburb of Greenwood Village. Loading

Megan Levy, AAP, Reid Sexton, Gerard Wright and Glenda Kwek

* Support is available for anyone who may be distressed by calling Lifeline 131 114, Mensline 1300 789 978, Kids Helpline 1800 551 800