Bronislaw Karpinski, Kamien Pomorski's mayor, said one woman still remains unaccounted for.
Donald Tusk, Poland's prime minister and Lech Kaczynski, the country's president, visited the town on Monday.
Tusk promised aid that would include "not only new housing, but also material aid to victims' families".
On Easter Monday, in overwhelmingly Catholic Poland, he called on "everyone to show respect for the tragedy and show proof of solidarity with the families with sober celebration of this holiday".
At least 77 people were staying at the hostel for homeless people and poor families when the blaze broke out.
Daniel Kowalinski, a local fire service spokesman, said: "The fire spread at an incredible speed. People could not leave their rooms.
"The hallways were on fire and filled with smoke. Parents threw their children through the windows so firefighters and witnesses could catch them."
Many of those injured had leapt from the windows and suffered bone fractures
An 18-month-old child was among those hurt but was in "satisfactory" condition, according to a doctor cited by TVN24, a Polish television channel.
Fratczak said it was Poland's deadliest fire since a 1980 blaze at a home for the mentally ill in north-central Gorna Grupa that killed 55 people.
"The injured were mainly people who fled the burning two-storey building even before the firefighters arrived," Fratczak said.
Firefighters continued to search through the ruins on Monday and the cause of the fire had not been determined, with police and prosecutors still investigating.
About 80 per cent of the building was in flames when firefighters arrived from a nearby station a couple of minutes after receiving the alert.
The burning building was constructed in the 1970s as a workers' hostel and transformed into a shelter several years ago.
Its roof and two storeys partially collapsed in the fire.
Firefighters said a number of people managed to escape by using an emergency stairwell.