Delta Airlines has enlisted the help of the Federal Bureau of Investigation to determine how sewing needles ended up in five turkey sandwiches served to passengers on four different flights on Sunday.
According to the Associated Press, one passenger was injured by a needle but declined medical attention. ABC News reports that passenger, James Tonges, has been placed on the newly-approved anti-HIV drug Truvada as a precautionary measure.
All of the affected flights originated in Amsterdam, Netherlands. The injured passenger was en route to Minneapolis. Two other flights were bound for Atlanta, and one was headed to Seattle.
In a written statement, the FBI announced that it was investigating the incidents.
Delta spokeswoman Kristin Baur released a statement in which she said that security for the airline's meal preparation service has been increased, as has use of pre-packaged food items pending the outcome of an investigation.
"Delta is taking this matter extremely seriously and is cooperating with local and federal authorities who are investigating the incident," the statement said. "Delta has taken immediate action with our in-flight caterer in Amsterdam to ensure the safety and quality of the food we provide onboard our aircraft."
That caterer, Gate Gourmet, also issued a statement.
"We take this matter very seriously, and we have launched our own full-scale investigation." The company also vowed to strengthen its "already stringent safety and security procedures to prevent any recurrence."
According to CNN, the US Transportation Security Administration (TSA) has notified all US-bound flights originating in Amsterdam's Schiphol Airport of the incidents.
Immediately after the discovery of the needles, Delta ordered all 18 of its flights from Amsterdam to stop serving the sandwiches.