Police said all 15 passengers of the single-engine banca were on their way to Placer town for a Roman Catholic Church activity when the accident happened.
Police identified the fatalities as Fabia Villamor, Gellyn Tunjao, Marlon Paniamugan and Gelorio Sajuga.
The 11 survivors were visibly shaken by the ordeal but were reported unharmed after the police conducted search and rescue operations.
Meanwhile, regional police headquarters in Butuan City assured local and foreign tourists to the Caraga that adequate security measures are being implemented to ensure the safety of tourists during the Kaliguan Festival set for June 21-24 at Cagwait, Surigao del Sur.
The annual Kaliguan Festival will be held at White Beach Resort in Cagwait, one the more popular tourist destinations in the Caraga region.
Caraga regional police chief, Alberto Olario said extra security measures are already underway in anticipation of around 2,000 local and foreign tourists who are expected to troop to the festival.
The Caraga region is gaining a reputation as being among the best surfing areas in the country but authorities are alarmed by the possibility that terrorist activities may disrupt the festivities.
The police undertook extra security measures after a group of armed men attacked the Barcelo Pearl Farm on Samal Island off Davao City and bandits kidnapped 20 tourists, including three Americans, and resort employees from an island resort in Palawan.
Olario said additional police units will also be posted along the boundaries of Agusan del Sur and Surigao del Sur following sightings of Muslim secessionist rebels in the area.
Olario said these areas are known to be the favorite escape routes of Moro Islamic Liberation Front (MILF) rebels operating in neighboring Davao Oriental.