Two young children died over the weekend after being found unresponsive inside a pickup truck.

Twins Oliver and Aria Orr, 3, were discovered by neighbors inside the vehicle, which was parked outside their home in Bossier City, Louisiana.

The mother of the children was inside the house at the time, and had been calling people who lived in the area to ask if they had seen the little boy and his sister.

Their tragic deaths come just three weeks after young Oliver was released from the hospital after suffering a near-fatal injury.

Police are now investigating the incident, and the cause of death has not yet been released pending autopsies.

The father of the children, Travis Orr, is a deputy at the Bossier Sheriff's Office. He has another child as well, son Maddox.

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Tragedy: Twins Oliver and Aria Orr, 3, died on Saturday after being found unresponsive inside a truck parked outside their home (twins above earlier this year)

Horrible scene: The two were discovered by neighbors (truck above) while their mother was inside calling people in the area looking for the two

Recent: Oliver had just been released from the hospital three weeks prior (above) after suffering a sudden and near-fatal injury

The Bossier City Police Department said in a statement that the neighbors found the children around 3pm on Saturday after 'the children’s mother, who was home at the time, had contacted them saying she was looking for the children.'

Emergency personnel arrived on the scene soon after and the two were rushed to a local hospital, where they were both pronounced dead.

'The investigation into this incident remains ongoing,' said the statement.

'Autopsies will be conducted to determine the cause of the death.'

The father of the children posted photos on Facebook last month after son Oliver ended up hospitalized after he suffered a sudden injury.

In one of the photos he is seen 'waking up' according to his father and there is a neck brace on him and breathing tubes coming out of his nose.

There is also a video of Travis telling his son to 'wake up' that he posted on social media.

Man in blue: The children's father, Travis Orr (above in NBC 14 video), is a deputy with the Bossier Sheriff's Office

Answers: Police are now investigating the incident with the cause of death not yet known until autopsies are complete (twins above during their first year)

The boy was in the hospital for over a week, and after his release his father posted a note on Facebook.

'Well we're home. Oliver was discharged today. I want to thank BCFD/EMS & BCPD for their quick response last Sunday night,' wrote Travis.

'The doctors and nurses at University Health for the outstanding treatment and care that Oliver received the last week.'

He closed out the post by writing: 'Oh and by the way other than the scratches and bandages, Oliver is back to full speed chaos.'