Malaysia’s transport minister called possible pings that might be linked to missing Flight MH370 the “most promising lead we have had” on Monday and said he was unable to rule out that some of its passengers remained alive.

“Miracles do happen,” Hishamuddin Hussein told a media briefing in Kuala Lumpur. “We continue to hope and pray for survivors. We are just hoping against hope.”

Hishamuddin had earlier been asked by a journalist whether the Malaysia Airlines jet may have landed on water, giving its crew and passengers time to board life rafts.

However, he added that leads received from satellite did not “indicate or show survivors.”

Hishamuddin said that investigators were “cautiously hopeful” that there would be more news within “days, if not hours” about whether the signals consistent with transmissions from aircraft black boxes detected Sunday were related to the missing airliner.

“I urge all Malaysians to unite in their prayers and not give up hope,” he added. “We have been through a real rollercoaster ride on some of the leads we have received. I am more optimistic about this one.”

The Beijing-bound Boeing 777 was carrying 239 people when it vanished on March 8.

— Henry Austin and Jason Cumming