An Amazon delivery driver was bitten by a large rattlesnake while delivering a package to a Florida home Monday night, according to the Martin County (Fla.) Sheriff’s Office.

The driver was delivering to a home in the Highland Reserve community of Palm City, south of Port St. Lucie on Florida’s east coast on Monday evening.

The snake, coiled up near the front door, struck as the driver bent down to set the package down.

She was bitten on the back of the leg, just above the knee, according to the MCSO. She immediately fell ill and called 911 for help. Determining the driver’s exact location through her phone’s GPS coordinates, first responders were dispatched to the location and the woman was transported to a hospital.

At last report, the woman was listed in “very serious condition,” according to the sheriff’s office.

Photos show a Martin County deputy wrangling the snake, still on the front porch of the home.

“Our thoughts are with the driver and we hope for a full recovery after this frightening incident,” Amazon spokesperson Branden Baribeau said in a statement.

“Together, with the Delivery Service Partner, we’re looking into the circumstances surrounding this incident and continue to make sure that drivers understand they should not complete a delivery if they feel unsafe.”

Eastern Diamondbacks are common to the southeastern U.S. and are the longest, heaviest venomous snake in North America, according to the Smithsonian.

It’s known for its iconic rattle and venomous bite, which can be fatal to humans. They average 3-6 feet in length, with some reaching up to eight feet, and can live for 20 years or more.