A 53-year-old Swede who told the FBI that his son-in-law had links to Al Qaeda was convicted of criminal defamation Thursday and sentenced to three months in prison.

The Lund District Court also ordered the defendant to pay $9,450 in damages to his son-in-law as well as some legal costs. The defendant was not named by police in line with Swedish privacy rules.

He had acknowledged sending the FBI an anonymous e-mail in which he said the younger man had links to Al Qaeda and supported the "Muslim world's revenge on U.S. terror."

The tip-off resulted in the son-in-law being stopped by immigration officials during a business trip to Orlando, Fla., in August 2006, and sent back to Sweden after interrogation.

The defendant told the court that he thought his son-in-law could have terrorist links partly because he liked to play war games on his computer. He added that he didn't think that U.S. authorities would act on the tip before carrying out their own investigation.

The court said the 53-year-old had no valid reason to suspect any Al Qaeda links and found him guilty of gravely defaming the younger man.

"There is no doubt that the information, through its content, was meant to cause serious harm," the court said.

It was not clear whether the man would appeal. His lawyer did not immediately return phone calls seeking comment.