Ervin Lupoe had a plan to move his family far from California, where mounting debt and sudden unemployment had left him desperate.

Police say something made him choose death for all of them instead.

Lupoe had pulled his kids from school, packed his sport utility vehicle with winter gear and appeared ready for a trip to his brother-in-law's home in Garden City, Kan.

It's not yet known if he was planning on leaving for good in a bid to flee his problems or if the trip would have only been temporary.

But instead, police say, he shot his five children and wife to death before turning the gun on himself.

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"Something happened in the last 48 hours that made him snap," Detective David Cortez, the lead investigator in the case, said Wednesday.

Investigators found evidence of spiraling financial woes. Lupoe owed the Internal Revenue Service at least $15,000 and a check he wrote the agency for that amount had just bounced.

He also was at least one month behind on a mortgage for his home in Wilmington, near the ports of Los Angeles and Long Beach. Jobs are scarce in the area and the real-estate market is sinking. Lupoe owed about $2,500 and a late fee, Cortez said. He also owed thousands more on a home equity line of credit.

Police found the bodies of Lupoe, his wife and five children Tuesday morning. Evidence suggests Lupoe probably shot his wife, Ana, first then killed his children. He appeared to have attempted to muffle the sound of gunfire by shooting a semiautomatic handgun through a pillow.

"It looked like they were all caught by surprise," Cortez said.

On a bed in an upstairs bedroom, the bodies of twin 2-year-old boys, Benjamin and Christian, were found beside their dead mother. In another bedroom, the bodies of 5-year-old twin girls, Jaszmin and Jassely, and their 8-year-old sister Brittney lay on a mattress pad next to their lifeless father.

Neighbors told police they thought they heard firecrackers going off between 4 p.m. and 6 p.m. Monday, meaning Lupoe was likely home with the bodies of his slain family for more than 12 hours before he killed himself.

Lupoe phoned his brother-in-law Monday morning saying he was on the way to Kansas, though it's not thought he actually left, Cortez said. Caesar Ramirez asked to speak to his sister but Lupoe declined. The next he heard from Lupoe was a phone call Tuesday morning saying he'd just killed his family and he left everything, including a small settlement from a traffic accident, to his brother-in-law.

Ramirez called Garden City police who contacted Los Angeles police, Garden City police Sgt. Michael Reagle said.

Lupoe, 40, and his wife Ana, 38, a Guatemala native who'd been living in the U.S. for at least 17 years, had both recently been fired from their jobs at Kaiser Permanente Medical Center West Los Angeles.

Kaiser Permanente spokeswoman Diana Bonta said the couple were fired after an internal investigation found they forged supervisors' signatures. They also misrepresented their income on documents provided to a nonprofit agency that provides assistance for child care, she said.

Lupoe faxed a bitter two-page letter to a local TV news station the morning he killed himself, saying a hospital administrator told him he "should not even have bothered to come to work" and "should have blown (his) brains out."

Investigators interviewed the hospital administrator, who said Lupoe's characterization of their conversation was an out-of-context misrepresentation and she denied saying what Lupoe said she did.

In his letter, Lupoe went on to suggest it was his wife's idea to end the family members' lives.

"He had one of those victim mentalities," Cortez said. "There is nothing yet that suggests his wife was a willing party."