Motivational speaker Jeff Locker phoned his wife at their Long Island home Wednesday night, telling her he had a flat tire and he'd be a little late. When he didn't return, she called police. Locker was found hours later, stabbed to death in his car in East Harlem in a possible botched robbery.

Now, police are trying to determine exactly what he was doing in the area in order to track his killer.

Police said Locker told his wife that two people helped him with the flat on his 2007 Dodge Mangum, and that he was going to drop them off before returning home, possibly from New Jersey. But it didn't appear the vehicle had a flat tire when it was discovered near the Wagner Houses in East Harlem.

Investigators were also looking to talk to witnesses who told reporters they saw Locker at a nearby deli purchasing condoms and bottled water around 3 a.m. Thursday morning, and that they had seen the car there before.

The 52-year-old North Woodmere, N.Y., resident was found with his hands bound behind his back with an electrical cord. He died from multiple stab wounds to the chest, with injuries to the heart, lung, liver and aorta, according to the medical examiner's office. Police wouldn't say why they believed it was a possible robbery.

His wife Lois left her home early Friday without speaking to reporters, and previously referred reporters to her husband's Web site. He also has three children.

Locker's Web site described him as dedicated to "bringing spirituality into the business world." He offered workshops on dealing with stress, frustration and anxiety in the workplace. Major companies around the country have hired him to speak, according to the site.

The site also said that he co-authored a spiritual self-help novel called "Teachings for a New World" and was a radio talk show host.

"Jeff finds balance in his life by being an avid golfer and a devoted, participating father to his two sons and his little princess," according to the site.

But Locker also apparently had serious legal troubles.

A federal bankruptcy court trustee in Florida sued Locker in April, identifying him as one of the investors who profited from a giant Ponzi scheme run by Louis Pearlman, the impresario who created boy bands 'N Sync and the Backstreet Boys.

The trustee demanded that Locker give back at least $121,200 of about $373,000 in bogus profits.

Locker said in a response filed in May that he categorically denied "all aspects" of the suit, and said he had no way of repaying the money. The case was pending.

"I would be forced to declare bankruptcy. I am severely in credit card debt and my business is just paying my family's bills."

He added that he was "mortified" to have been accused of knowingly participating in a Ponzi scheme.

"I trust that the court will honor this answer to the complaint based on the facts presented herein so that I can get on with my life."