The author of the letter that led to the mistrial in the Tyco (TYC) case told police he thought a mistrial already had been declared when he wrote it, a police official told The Associated Press on Tuesday.

The letter was sent last week to juror Ruth Jordan (search), who according to other jurors had favored the defense during much of the deliberations.

The letter expressed anger at the 79-year-old Jordan, who had been identified by some news organizations, for appearing to favor the acquittal of Dennis Kozlowski (search) and Mark Swartz (search), who were charged with looting Tyco International Ltd. of more than $600 million.

The missive prompted Justice Michael Obus to abort the six-month-long trial. Obus declared a mistrial Friday after 11 days of deliberations, citing outside influences on the jury.

The letter "was signed by a person who thought there was already a mistrial and was complaining to her about it," said the police official, who spoke to the AP on condition of anonymity.

The police official, who had not seen the letter but had been briefed on the investigation, said the letter was not threatening.

"It wasn't a death threat," the police official said. "It probably doesn't rise to the level where there would be a prosecution but that's the DA's call." Among the potential charges could be jury tampering.

The letter remains under court seal.

The Wall Street Journal and The Washington Post first reported about the letter writer's claim in Tuesday's editions.

There was no immediate response from Jordan. An answering machine at her home was full and would not take a message.

Jordan was thrust into the spotlight when several news organizations published her name after she made a gesture that some observers thought was an "OK" signal to the defense team.

The gesture came a day after notes from the jury to the judge declared that deliberations had become "poisonous" and suggested that one juror, later identified as Jordan, was steadfastly in favor of acquittal and unwilling to deliberate. According to jurors' accounts, she later became more cooperative and jurors were on the verge of returning a mixed verdict on some of the dozens of charges when the mistrial was declared.

The Manhattan district attorney's office has refused to comment other than to say it would seek to quickly retry the defendants.