BANGKOK -- A Thai air force radar station has detected the signal of an unidentified aircraft that departed from Malaysia and flew northward but later diverted possibly to the Strait of Malacca, air force chief Prajin Juntong said Tuesday.

The radar in the southern province of Surat Thani detected a passenger aircraft that diverted and passed the port city of Butterworth in Malaysia, Prajin was quoted by the Nation newspaper as saying.

The aircraft could have flown to the Strait of Malacca, he said, adding it remains to be confirmed whether it is the missing flight MH370 operated on a Boeing 777-200 with 239 people aboard.

The information has been passed to the Malaysian air force, Prajin said.

In addition, caretaker Foreign Minister Surapong Tohvichakchaikul said Tuesday he was expecting a call from his Malaysian counterpart concerning the cooperation in searching for the missing jet.