A dog was shot and killed inside his owner’s home — all because of a door that wouldn’t stay shut.

Police in Round Rock, Texas, responded to a home alarm being set off on Friday, announced themselves and entering the home.

Inside, they found no burglar — the homeowner later said the alarm was probably set off by the faulty front door coming open accidentally — but they did encounter a Rottweiler named Bullet, KTBC-TV reported.

Image source: screengrab via KTBC-TV.

Image source: screengrab via KTBC-TV

The encounter ended tragically.

“They killed my best friend,” said the homeowner, Russell Lane.

Russell Lane, left. (Image source: screengrab via KTBC-TV)

Russell Lane, left. (Image source: screengrab via KTBC-TV)

Lane was at work when the alarm went off; he got a notification on his phone and deactivated the alarm.

But a few moments later, a neighbor called to say they’d heard gunshots from inside Lane’s home.

“I understand if he got out and you were scared for your life because he was an aggressive dog, and you kill him out in the streets to protect someone but you don’t come in this dog’s house in his place and murder him,” Lane told KTBC-TV.

According to police, Bullet acted aggressively upon seeing the cops inside the house, and a pair of officers fired seven shots at the Rottweiler, hitting him five times.

Police removed Bullet’s body from the home, and Lane said he planned to cremate his dog.

“I can assure you, they won’t get away with killing Bullet in this house,” Lane said.

Police say they are investigating the shooting.

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