JAKARTA - A boat carrying some 50 people was capsized in Mahakam river, East Kalimantan at 18:00 middle Indonesian time Wednesday afternoon.

Spokesperson of Indonesia's National Disaster Mitigation Agency Sutopo Purwo Nugroho said that 41 people were still missing at the moment and one female body had been retrieved from the capsize site at Harapan baru village in Loa Janan Ilir subdistrict in East Kalimantan province.

Sutopo said due to the lack of passenger manifest, rescuers faced difficulty in finding out the exact number of people on board the ill-fated board. Eight people had been saved by the rescuers by far.

Leaks in the boat were suspected to be the reason for its capsize.  

"The victim found dead at the scene was Nurhayati, 41. Eight people have been saved and 41 others were still missing. The absence of passengers manifest made us only guess the total number of people onboard the boat," Sutopo told Xinhua by phone.

He said the boat had been used to transport the workers daily from one side of Mahakam river to the opposite side, adding that search efforts was temporary stopped due to strong wind and strong river stream at capsize site.

According to him, the search operation was jointly conducted by regional BNPB and National Search and Rescue (Basaranas) officials, volunteers, public order police (Satpol PP) and amateur radio communication organization of ORARI.

Some speed boats have been ready at the location for retrieving the victims.