A sharp-eyed delivery van driver who spotted "Call 911" written on a package helped save a woman who was being held captive by her husband at her home in Robertsville, Missouri on Tuesday (Dec 6).

The driver, who works for package delivery company UPS and who did not give his name, picked up a package from the woman at her door.

Scrawled on top of it were the words "Call 911".

He alerted the police, and a SWAT team was dispatched to the home, where they found the woman and her three-year-old child being held captive by her husband.

Her husband, James Tyler Jordan, 33, was taken into custody, CNN reported the police as saying on Friday (Dec 9).

Jordan was allegedly suicidal and had refused to let his wife leave the premises, physically and sexually assaulting her, according to court documents.

Court records say that Jordan allegedly put a gun to his wife's head and threatened to kill her, news site kmov.com reported on Thursday (Dec 8).

The driver has been praised both by the police and UPS.

Franklin County Sheriff's Department Sergeant T. J. Wild told kmov.com that "he was a huge help".