Personal information about Los Angeles police commanders has been posted on the Internet, prompting an investigation into where it was obtained, an LAPD spokesman said on Wednesday.

The disclosure comes during a recent rise in attempts to hack into the department's website, Lieutenant Andrew Neiman said, but the recently posted details did not appear to have been gleaned from LAPD computers.

We're looking into what sources they have retrieved it from. It doesn't look like they accessed any department databases, he said, adding that he was unaware of any successful recent hacking of LAPD computers.

Investigators were trying to determine who made the posting, Neiman said, adding that at least some of the information was likely taken from public sources.

If it's public record it's pretty tough for you to enforce, but it's a concern for members of law enforcement having their personal information out there, he said.

Neiman declined to identify the website. A web page similar to the one described by police had been deleted as of Wednesday afternoon.

A second posting on Monday, possibly by the same person or group, listed the names and email addresses of dozens of high-ranking Los Angeles police officers.

Hackers have in the past made public the personal information of authorities, including a University of California, Davis campus police officer who was suspended last month after pepper-spraying student protesters.

Neiman said police officers in the past had also unwittingly revealed personal information on social networking sites.

We try to provide some education to our officers all the time, he said. We remind our officers to do their best to protect their identities and the identities of their family members.

Neiman said an officer who runs the department's website had noticed a slight increase in attempts to hack into it but none of them had been successful.