Jakarta, Indonesia (CNN) -- Fifteen bodies were recovered Saturday from the wreckage of an airplane that crashed into the ocean while preparing to land in the Indonesian province of West Papua, officials said.
Rescuers were searching for survivors of the Merpati Nusantara Airlines crash just off the coast of Kaimana, said Bambang Ervan, a spokesman for the Indonesian transportation ministry.
There were 21 passengers and six crew members aboard the plane, a turbo-propeller MA60, he said.
Ervan could not immediately confirm any casualties, though a Kaimana Airport ticket agent told CNN that at least 15 bodies have been recovered.
The agent, identified as Polly H., said there were children among the casualties, though she could not say how many.
Among the passengers on the flight were 18 adults, two children and one infant, Ervan said.
Search and rescue teams were still searching the waters off Kaimana for survivors, the ticket agent said.
The plane crashed shortly before 2 p.m. local time. The cause of the crash was under investigation, Ervan said.
Merpati, a cash-strapped state-owned airline with an aging fleet, flies many of the more remote routes in Indonesia.
In 2010, a Merpati airplane overshot the runway at the Rendai airport in Manokwari, West Papua, injuring 78 people.
A year earlier, two Merpati planes crashed within two months of each other in Papua.
The first occurred in July 2009 when a Merpati flight lost its front wheels as it took of from Biak. A month later, another flight -- a Twin Otter aircraft -- crashed, killing 16 people on board.
Indonesia has made efforts in recent years to improve its safety record.
CNN's Kathy Quiano contributed to this report.