Jakarta, Dec. 28 -- Rescue teams searching for four Spanish nationals missing after a boat accident in eastern Indonesia have found items believed to belong to the vessel, as authorities widened the operation on its fourth day amid challenging sea conditions.

Indonesia's National Search and Rescue Agency (Basarnas) said items recovered during the operation included a life jacket and parts of the upper structure of KM Putri Sakinah, the boat that sank in waters off Labuan Bajo, East Nusa Tenggara.

The coordinator of the West Manggarai SAR Post, Edy Suryono, told reporters in Labuan Bajo on Sunday that the items were found south of the accident site and had been confirmed by the ship's captain as belonging to the vessel.

"South of the in...