At least six bodies and wreckage including a plane door and oxygen tanks have been recovered in the search for missing AirAsia Flight QZ8501.
The bodies - which were not wearing life jackets - have been brought on board a navy ship, said Indonesia's search and rescue director SB Supriyadi.
Local television showed pictures of the bodies floating in the sea.
"The warship Bung Tomo has retrieved bodies and the number is growing. They are very busy now," said a navy spokesman.
They were found in the Java Sea southwest of Borneo, about six miles (10km) from where the plane last communicated with air traffic control.
Search chief SB Supriyadi also said the air force had "found an object described as a shadow at the bottom of the sea in the form of a plane".
An expert from the UK's Air Accidents Investigation Branch is heading to the area with equipment to help detect the signal from the plane's black box.
Objects spotted earlier have also been confirmed as wreckage from the plane and some have been taken away for testing.
AirAsia boss Tony Fernandes tweeted that his "heart is filled with sadness" and rushed to Surabaya airport to meet distraught relatives.
"It's an experience I never dreamt of happening and it's probably an airline CEO's worst nightmare," said Mr Fernandes.
"The passengers were on my aircraft and I have to take responsibility for that,"
The Airbus A320-200 disappeared from radar on Sunday morning on its way from Surabaya, Indonesia's second-biggest city, to Singapore.
There were 162 people on board, including one British man , Hull-born Chi Man Choi, and his two-year-old daughter.
The aircraft's last request - to climb higher to avoid a storm - was turned down.
Minutes later it fell off the radar without giving any distress call.
Pilots say the area is often referred to as the "thunderstorm factory".
Geoffrey Thomas, editor of AirlineRatings.com, told Sky News the plane may have stalled after struggling to maintain speed.
"We have a radar plot which shows the plane actually climbing through 36,300ft - it wasn't given permission to do that.
"It also shows that its speed had decayed by 134mph and dropped dramatically to a level where it couldn't sustain flight."
Some 30 ships and 21 aircraft from South Korea, Singapore, Malaysia, Australia and Indonesia have been involved in searching 10,000 nautical miles of ocean.
Indonesian President Joko Widodo told a news conference a "massive" operation to retrieve the remaining bodies would start at first light.
It is hoped the black box, which records cockpit voices and crucial flight data, will be easy to find as the plane is believed to have crashed in shallow seas.