Katie Holmes is concerned she is being watched by private investigators hired by Scientologists.
The former Dawson's Creek actress filed for divorce from husband Tom Cruise - a famous devotee to the sci-fi faith - late last week, but is now worried her actions are being monitored due to a car parked outside of her apartment building in New York with a number of "suspicious-looking" men inside.
A source told The Sun newspaper: "About three days before the divorce was announced a Mercedes SUV was sitting outside Tom's apartment in Greenwich Village.
"They were sat about a hundred yards from the house - a couple of suspicious-looking characters in sunglasses.
"When Katie came out they tried to discreetly follow her. It was obvious they weren't paparazzi or press.
"They looked like former military or police and were carrying a small pocket digital camera."
Katie - who is reported to be asking for sole legal and residential custody of their six-year-old daughter Suri - was so anxious she had her own security people take photographs of the men and forward them to the police.
The source added: "Katie's security came out and started recording the men. Then police were called and went back to the car to ask them what they were doing."
The 33-year-old actress is believed to have become tired of Tom's devotion to the quasi-religion - also followed by John Travolta - causing her to ask for the divorce as she wants what is best for her daughter.
The insider said: "Katie just wants the best for Suri. This is awful for her but she is being very brave. It's a terrifying situation for Katie."