ARUNKUMAR INGLE had planned to fake his own death, leave his family more than $3 million in life-insurance benefits, grab a fake passport and escape Delaware County to live with his mistress in India.

Instead, the 55-year-old Boeing engineer was found bludgeoned and stabbed to death in his Middletown home in January 2008, his blood splattered on the walls and his testicles severely bruised.

That's the story told in a 31-page criminal complaint filed yesterday - nearly four years later - that accuses Ingle's son of murdering him after installing a GPS device on Ingle's car and a keystroke logger on his computer to monitor the long-running affair.

Parth Ingle, 25, was charged with first-degree murder and related crimes and is being held without bail at the George W. Hill Correctional Facility in Thornbury Township.

"It's not as you would see on TV where you solve it within an hour. You're talking about DNA, computer analysis, forensic analysis, blood-spatter analysis," said State Police Lt. Anthony Sivo, in explaining the lengthy investigation.

Parth Ingle, of East Coventry, Chester County, was convicted in October of cyber-stalking his father, but was sentenced only to probation and community service. Prosecutors want to put him away for life on the murder charge.

Civo and Delaware County District Attorney G. Michael Green declined to elaborate in detail on the affidavit, which describes Parth Ingle's statements as evasive and inconsistent but includes little physical evidence tying him to the murder scene. Civo said Parth Ingle allegedly killed his father for money and because he was angry about the affair.

"Just because he has a little bit of debt, like half of America, he killed him?" asked Parth Ingle's attorney, John E. Kusturiss Jr. "Parth did everything to keep the family together. He didn't do anything to hurt his father."

Arunkumar Ingle's former mistress testified at Parth Ingle's trial this year that she was planning to move to India with Arunkumar after he faked his own death. She said she didn't know he was married until Parth Ingle came to her Philadelphia house in 2007 to confront his father.

Ingle's body was found by his wife, Bhavnaben, who came running out of the house screaming to her daughter about "blood," "dad," and "everywhere," according to the criminal complaint.

When she spoke to police hours later, she held an icepack because her hands hurt from clutching them so hard in response to the discovery.