WATCH: 'It wasn't me,' said Sri Lankan American entrepreneur Moonesinghe before being shot by Austin police officer

A video emerged of a wealthy Sri Lankan American entrepreneur being fatally shot by a police officer in Austin while he was defending his house from a suspected burglar.

As Rajan Moonesinghe lay dying, he can be heard saying: “It wasn't me.”

The killing, described by Austin Mayor Steve Adler as a “tragedy”, took place when the co-founder of the fintech firm InKind was on the front porch of his house.

A private security guard of his neighbour across the road called the police to report Moonesinghe who was wielding a gun.

The guard told a dispatcher: “He almost seems to be scared of something inside his house.”

“He's pointing the rifle at the interior of his home,” the guard said over the phone. This was followed by Moonesinghe calling into his living room and firing shots inside.

Daniel Sanchez, one of the two police officers who arrived at the scene within minutes shouted: 'Drop the gun.'

But the officer shot Moonesinghe before completing the sentence.

He was taken to a hospital where succumbed to his injuries and a preliminary autopsy report revealed the victim was hit four times. No one else was hurt in the incident.

Moonesinghe had moved to the South Austin neighbourhood about five years ago. InKind, which he set up with his brother Johann, provides upfront financing to restaurants.

Jon Blum, a former police officer, told the Wall Street Journal that the bullet had hit Moonesinghe “before he heard anything because bullets travel faster than sound.”

Sanchez has been on administrative leave since the incident and the attorneys of Combined Law Enforcement Associations of Texas representing him said the licenced police officer “followed his training in order to protect lives.”

Doug Ludlow, the CEO of small business-assistance company MainStreet told the WSJ: “There is massive competition to create new startup hubs. If it's not a safe community, especially for people of colour, you will not create a tech hub here. Full stop.”

Johann said his family would do “whatever it takes” to get their voice heard.

“When Raj was buried, I made a promise to him. I said, "Raj, I will be an unstoppable force of justice for you. And I will make sure this doesn't happen to another family,"' he said.