Reaching the slopes of an active volcano, where a small aircraft is believed to have crashed, has been a struggle for rescuers, according to the officials.
On Saturday, a Cessna 340 plane carrying four people went missing shortly after taking off from Bicol International Airport in Albay province, several kilometers from Mayon volcano.
The Energy Development Corporation, based in Manila, said the missing plane belonged to them and that they were looking to confirm whether the wreckage discovered on Sunday in "very steep terrain and at a high altitude of about 6,000 feet" was theirs.
According to Bicol police, two of the four passengers on board the missing plane were Australian, and rescue teams with sniffer dogs had been deployed to find the crash site.
Cedric Daep, an Albay disaster officer, said a Cessna plane was seen 300 to 350 meters (984 feet to 1,148 feet) from the crater.
However, he warned that the rumbling volcano could erupt at any time, complicating rescue efforts.
An aerial search for the missing people will resume on Monday.
Another Cessna plane went missing in the northern province of Isabela last month, on January 24.
The wreckage of that plane has yet to be discovered, according to Apolonio.
