Police are investigating the shocking drownings of up to 14 children who were out in rafts on a lake in northwest Russia despite a storm warning. Karelia, where the tragedy took place, and Moscow, where the victims were from, have declared a day of mourning.

Follow RT's LIVE UPDATES on Russian tourist boat disaster

UPDATE: Russian authorities have published a preliminary list of the 14 victims’ names, with their final confirmation pending. The bodies have been flown to Moscow, where they will be identified on Monday.

Earlier, the head of the Republic of Karelia, Aleksandr Khudilaynen, said that 13 children have been confirmed dead and one was unaccounted for. Khudilaynen spoke at an operational meeting early on Monday.

Investigators say there were 47 children and four adults on board the vessels: two boats and one raft. All of them were from the Park-Hotel Syamozero summer camp located on Lake Syamozero, not far from the border with Finland.

A total of 37 people from the three boats survived the incident, according to the Emergencies Ministry. Up to 350 rescuers were working at the scene.

The ministry said that 12 children have been hospitalized in Petrozavodsk and another 21 are being accommodated at a cadet school, where they are receiving medical aid and food.

“Out of 33 [rescued] children, 12 were taken to medical facilities. There is no threat to their life,” said Igor Panin, head of the Northwest Regional Center of EMERCOM.

The drowned children were from Moscow, Mayor Sergey Sobyanin confirmed on Twitter, expressing condolences to their families and friends.

Moscow authorities have sent rescuers, doctors, psychologists and social workers to the scene.

Identification of the children who died in the Karelia lake disaster will be carried out in Moscow on Monday, the Moscow social security authorities have said. The children who survived the trip will be also brought to Moscow on a special charter flight provided by the Emergencies Ministry.

DETAILS: Incident took place at lake Syamozero, large freshwater lake in Republic of Karelia https://t.co/kG03PS0dXvpic.twitter.com/atsLaRdCix — RT (@RT_com) June 19, 2016

All of the victims of the Karelia boat disaster were children born between 2002 and 2004, who were staying at a camp, Vladimir Markin, the Investigative Committee spokesman, said.

There were no adults among the dead, he stressed, denying earlier reports that one of the instructors had died.

The kids, who died in the boat disaster, were between 9 and 11 years of age, Aleksey Gavrilov, deputy head of the Committee on Education, Culture, Sports and Youth Affairs at Karelia’s Legislative Assembly told RT.

Children’s rights ombudsman Pavel Astakhov has confirmed that orphans were among the children who died in a lake boat disaster in Karelia.

Earlier, Rosturism state agency said that, according to preliminary data, the deceased kids were orphans and children from troubled families.

She held brother's hand throughout: 12yo girl survives Russian lake disaster, raises alarm https://t.co/6SJrIAKXlMpic.twitter.com/KJ9UtnTVLy — RT (@RT_com) June 19, 2016

Four suspects connected with the tragedy at Syamozero have been detained in Karelia, Vladimir Markin, the Investigative Committee spokesman, said.

They are the head of the Park Hotel Syamozero, Elena Reshetova, her deputy, and two instructors, he added.

“Within the framework of a criminal investigation, a legal assessment will be given to the actions of the staff of the children's camp and other responsible parties, which send the children boating in bad weather,” the spokesman stressed.

This is not the first time the staff of Hotel Syamozero has been subjected to a criminal investigation, Markin said.

“Back in 2011 its deputy director beat a security guard to death after consuming alcohol together with him. Currently, he’s serving a 13-year sentence for the crime,” he explained.

Those children who died in the incident “apparently had no life vests” and those who “were with life vests managed to survive,” children’s rights ombudsman Pavel Astakhov told RIA.

“Now we are trying to figure out who gave permission for the journey, if all were provided with the life vests,” Astakhov added.

Russia hadn’t seen such a mass casualty incident in a summer children’s camp for several years, according to the omdudsman. “It is necessary to declare mourning in Karelia and Moscow,” he said. Karelia will hold a day of mourning on June 20, authorities said.

The fatalities on Lake Syamozero in Karelia could have been avoided if the boat trip had been properly registered, the press service for the North-Western Emergencies Ministry’s Regional Center told TASS.

"If the camp’s staff had warned the Emergencies Ministry of the boat trip, they would have been accompanied by rescuers or banned from boating due to weather conditions," the press officer said.

The rescuers learned about the disaster from the locals after one of the survivors reached a village on the lakeshore.

“If the group had been registered and wouldn’t have establish communication in due time, the rescue workers would’ve started the search immediately. But here time was lost,” the press service said.

Tatiana, a local resident, told RT that the boat trip was a bad idea because of the weather conditions.

“The wind was mad yesterday. It’s a crime to let children for a voyage on the lake,” she said, adding that the camp was not a place she would recommend people to send their children to. According to her, instructors at the camp were regularly drunk. She also mentioned that not long ago a security officer was killed on the camp’s premises.

Публикуем видео с места гибели детей в Карелииhttps://t.co/it5apRCVZVpic.twitter.com/eZ1Q0RaLtZ — Life | Новости (@lifenews_ru) June 19, 2016

A mother who once sent her son to the same camp told RT that her child got gangrene during his stay in the camp. The boy had a splinter and doctors at the camp weren’t able to remove it, she said.

She said there were other incidents of negligence, such as when the camp instructors left a child at a nearby station and his parent had to take him back home from there, not from the camp.

“There was no control in the camp. Drunk camp workers once broke a boy’s leg,” she said.

The incident was a “shock” for locals, Vita, from the tourist complex Qudaamah, where the rescued children were brought, told RT, adding that the surviving children are at the nearby base.