Updated

As some New Orleans police officers come under investigation for abandoning their posts in the wake of Hurricane Katrina and for allegations of looting, there are murmurings that outgoing Police Chief Eddie Compass (search) was forced to resign by Mayor Ray Nagin (search).

"Since I was a little boy, the whole time I've wanted to be the superintendent of police," Compass said Tuesday when he abruptly announced the end of his police career in the Crescent City. "I will be retiring as superintendent of police and I will be going on in another direction God has for me."

Click on the video box to the right for a complete report by FOX News' Steve Brown.

Compass didn't give a reason for stepping down. But the New Orleans Times-Picayune reported this week that unnamed police sources close to Compass said the former police chief told them that he allegedly got into an argument with Nagin Tuesday morning.

At the end of the dispute, Nagin asked Compass to step down, sources said. This would have been just hours before the news conference where Compass announced his retirement, after which Nagin called Compass a hero.

"I'm sure his wife is doing a dance right now," Nagin said Tuesday. "I trust he will make a lot of money ... and I hope he will at least send me a Christmas card now and then."

Asked about whether the Times-Picayune story is true, neither Nagin nor Compass offered any comment or statement. Officers on the force wouldn't speculate as to what happened, either.

"The only two people who know the truth are Eddie Compass and Ray Nagin, and neither one of them are talking," said David Binelli, president of the New Orleans Police Association.

The questions surrounding Compass' departure come at a bad time for the department.

Almost 250 of the officers who have been working nonstop for weeks are under investigation for being AWOL from their posts during Hurricane Katrina (search) and there is another probe into whether some on the force participated in looting in the chaos that followed the storm.

One incident allegedly took place at a Wal-Mart. Also under scrutiny is whether police appropriately took Cadillacs from a car dealer's lot to use on patrol. The Louisiana attorney general is also investigating the car use.

Click here for the Times-Picayune story about the police investigations.

"There is zero tolerance for misconduct or unprofessionalism by any member of this department," said Acting Police Superintendent Warren Riley. "When allegations surface ... there will be a complete and thorough investigation."