WASHINGTON (AP) — The Air Force says Italian rescue teams have recovered debris from the Adriatic Sea that is believed to belong to a U.S. F-16 fighter jet that went missing on Monday after taking off from a base in Italy.

The combined U.S.-Italian rescue effort has not found any sign of the pilot, according to a statement from the 31st Fighter Wing at Aviano air base.

The search is continuing.

The F-16 was on a nighttime training mission when the Air Force base at Aviano lost contact with it.