Malaysia’s civil aviation chief says no signs of the missing Malaysian jetliner have been found at a location where Chinese satellite images have shown what might be plane debris.

Datuk Azharuddin Abdul Rahman says planes searched the location on Thursday.

“There is nothing. We went there, there is nothing,” he told reporters in Kuala Lumpur.

Vietnamese officials previously said the area had already been “searched thoroughly” in recent days.

The hunt for the Boeing 777 has been punctuated by false leads since it disappeared with 239 people aboard just hours after leaving Kuala Lumpur for Beijing early Saturday.

The plane was heading east over the South China Sea when it disappeared, but authorities believe it may have turned back and headed into the upper reaches of the Malacca Strait or beyond.

Meanwhile Malaysia Airlines has retired the missing jetliner’s flight code as a sign of respect to the 239 passengers and crew on board.

The airline said it will no longer be using MH370 and MH371.

MH370 was used for Kuala Lumpur-Beijing route and MH371 for a return flight.

Starting on Friday, Malaysia Airlines said it will use codes MH318 and MH319 for twice-a-day flights to and from Beijing.

“Our thoughts and prayers remain with the families of our colleagues and passengers of MH370,” the airline said in a statement.