(CNN) -- The label on the package claimed that it contained T-shirts and baby toys.
When customs officials in Sydney scanned the parcel, they found five pythons and two venomous tarantulas.
But when customs officials in Sydney X-ray scanned the parcel, they found instead five pythons and two venomous tarantulas.
On Tuesday, authorities raided the house in Sydney to which the parcel had been addressed. Officials seized evidence but expect to file charges later, the customs agency said.
Importing live animals without a permit is illegal in Australia and can yield a 10-year prison sentence and a fine of 110,000 Australian dollars ($92,000 U.S.).
The parcel was sent from the United States last week, but officials would not say specifically where it had been mailed from.
The snakes were wrapped within white calico bags and the spiders were packed in clear plastic containers, the customs agency said.
The creatures were later killed because they posed a quarantine risk, the agency said in a press release.
It titled the press release: "Spiders and snakes on a plane."