When police arrived at the crime scene in suburban New York, mother and son were waiting for them at the driveway.
Inside the spacious home, they found the body of Mr Ling Tan, 49, CEO of Dynamax Imaging, a company that manufactures image sensors.
His 19-year-old son, Charles Tan, was charged on Tuesday with the murder of his father.
The Cornell University sophomore is being held without bail.
Mr Tan had been shot multiple times and a shotgun was found in the garage on Tuesday morning, according to sheriff's office spokesman John Helfer, NBC News reported.
The son "fired multiple rounds," blasting his dad in the face, neck, chest and arm on Monday evening, police said in court documents.
Tan's mother, Mrs Qing Tan, frantically called police to the spacious Pittsford house shortly before 6pm, the New York Daily News reported.
It is unknown where the 56-year-old was at the time of the shooting.
On Tuesday, investigators were spotted walking in and out of the house, which was surrounded by heaps of snow.
Police had been called to the home in the upscale suburb several times in the past for reported domestic incidents, Monroe County Sheriff's Office told newspaper Rochester Democrat & Chronicle.
The police declined to describe the nature of those incidents, but neighbours claimed they had heard family members shouting in the past.
One claimed she had seen Mrs Tan shoving her husband and yelling in the garden.
"I heard yelling numerous times - even with the house closed up," neighbour Samantha LiMuti told Rochester Democrat & Chronicle.
Tan studied in the Agricultural and Life Sciences department at Cornell.
Neighbours described him as kind and friendly.
"He is always a very nice boy," said neighbour Catherine Toy.
"I'm sure all the neighbours will support him."
Audio recordings of emergency calls, obtained by Democrat & Chronicle indicate that Tan - who is a member of Cornell's Sprint Football team - initially said he was defending himself from his father. He is scheduled to appear in court tomorrow.
The elder Tan had previously worked at Eastman Kodak for 20 years.
This article was first published on February 11, 2015.
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