BERN, Switzerland?A suspected anthrax letter sent to Chile bore a Swiss postmark but may have been mailed from New York, Swiss police said Wednesday.

Dr. Antonio Banfi, a pediatrician in Santiago, Chile, received the letter?with a Swiss postmark and a Florida return address?two weeks ago in what may be the first confirmed case of anthrax contaminated mail outside the United States.

The Centers for Disease Control and Prevention initially confirmed the contamination last week and was conducting further tests to determine whether the suspected spores in the letter to Banfi was from the same strain as anthrax found in letters in Washington and New York.

“We’re certain it’s anthrax but what strain of anthrax is something that’s very important to determine,” said Tom Skinner, a CDC spokesman in Atlanta. Test results could be returned by late Wednesday, he said.