Among the things you don’t have to be told not to do …

A shooting game between two friends in Texas has taken a tragic turn, with one dead and the other arrested for his murder.

Sean O’Donnell, 37, and Aaron Prout, 34, were taking turns shooting at each other with a rifle while wearing a kevlar helmet inside a Houston home on August 17.

The game unfolded at a home on Pennington Hills Drive in the northern outskirts of the city, but it went horribly wrong when O’Donnell allegedly fatally shot Prout, an English military veteran.

Harris County Sheriff Ed Gonzalez said deputies were called to the home and ‘found an adult male who sustained what appeared to be a gunshot wound to the head’.

‘He was transported to a hospital, but subsequently died from his injuries,’ Gonzalez said.

He added that Prout was a British expat living in Houston, while O’Donnell owns the property where the shooting took place.

‘Hard to believe two, so-called friends, would take turns shooting at each other wearing a kevlar helmet, inside a house in a residential neighborhood, while using a rifle,’ Gonzalez said.

He added that the incident was initially recorded as a potential suicide, but ‘things weren’t adding up’.

‘With thorough follow-up investigation, the truth was ultimately revealed,’ Gonzalez said.

Officials did not disclose the type of rifle which was used or the distance between the two friends at the time the deadly trigger was pulled.

It’s unclear whether the bullet missed the ballistic helmet, or if it penetrated through the armor.

A heartbroken relative of Prout’s said he served in the British Royal Marines for 10 years before moving to Texas, ‘the place he was happy and loved’.

‘The passing of Aaron has left me totally heartbroken, this was the worst news I have ever received,’ the relative wrote on Facebook.

‘Aaron was a very caring and wonderful person and was always there for his friends, he lived his life to the absolute fullest.

‘He had a brilliant job and was starting his own business. His passion was target shooting and he had won many tournaments .

‘Aaron always used to make me feel like a million dollars whenever I spoke to him, and made me laugh when telling me about all his wild and wonderful adventures.

‘He was renowned as one of the best pranksters, always with a smile on his face and a very kind heart.’

O’Donnell’s social media indicates that he is also a military veteran.

He was charged with murdering Prout and booked into the Harris County Jail on Thursday.

How could anyone do this unless he was under the influence of … something?