Police were called to the home of moviemaker Sam Taylor-Johnson and her actor husband Aaron on Thursday night (28Aug14) after a passer-by spotted a machine gun in the London property.
Officers attended the scene after receiving a report that an automatic weapon could be seen through a window.
However, it emerged the gun, which had been placed on a desk, was a fully decommissioned M16 rifle given to Taylor-Johnson as part of an art project.
Neither the director nor her Nowhere Boy star husband Aaron were at the property when cops called.
A spokeswoman for the couple tells the Bbc, "We can confirm that early this morning police were called to the London home of Mr. and Mrs. Taylor-Johnson following a report of a firearm on the premises by a concerned passer-by.
"The family were not present in the property at the time but the police gained entry via a key holder. The firearm was located in Sam Taylor-Johnson's basement studio and has been confirmed as a certified and fully decommissioned M16 assault rifle that was provided to Mrs. Taylor-Johnson by the international charity Peace One Day as part of an art project entitled Peace One Day M16."