NEW YORK -- Among the 2,792 names on the official World Trade Center death toll are 42 people actually listed as missing -- not dead -- because their remains have not been identified and their whereabouts on Sept. 11, 2001, cannot be established with certainty.

Some of those people may not be dead, or they may not even exist. A few may be trying to fake their deaths, while others could have been wrongly reported missing, city officials said in interviews with The Associated Press.

The remains of about 1,520 people have been identified, most of them by DNA, and 1,230 others were confirmed dead by the courts because families submitted proof to a judge that the victim was at the trade center or on one of the hijacked planes that crashed into the twin towers.

But 42 cases have no such proof and no identified remains. They will remain listed on the trade center death toll for now.

"Those cases stay open, and will stay open, until it has been declared a fraud, the person has been identified, or information comes up in another way that closes the case," said Shiya Ribowsky, deputy director of investigation for the city medical examiner's office.

The names of the missing will also be included in the list read aloud at Thursday's second-anniversary ceremony.

"If we can't rule it either way, it's better to have their name on there and pay respect to them if they did die," said Kenneth Ling, a police lieutenant pursuing the missing cases.

Days before last year's anniversary remembrance, the city released its first official victims' list. Relatives and dignitaries read aloud 2,801 names, pausing for four moments of silence to note the two airplane strikes and each tower's collapse, as they will this year.

By December, officials had removed nine names. One was a duplication, one was fabricated by a woman allegedly trying to defraud victims' charities and seven had been wrongly reported missing.

The police department, mayor's office, city law department and medical examiner's office formed a group called the Reported Missing Committee to weed out fraud and cross errors off the death list, which peaked at 6,700 two weeks after the attack.

New York police alone have made about 40 arrests involving people falsely claiming they lost loved ones, and law enforcement agencies in other cities have caught others.

The most recent name removed from the list for suspected fraud was Jeffrey Montgomery. Authorities say a Missouri woman invented a missing brother and collected $64,000 in charitable aid. She is being held on fraud charges.