What does "an individual's next of kin were informed" (5th paragraph) mean?

Context>>>>>
The scope of the tragedy became clear as police released the names and ages of those who died in one of Britain's worst incidents of people smuggling.

Two of the dead were only 15, while the oldest was 44. Some 20 of the victims came from one province — Nghe An in north central Vietnam, around 200 kilometers (120 miles) south of Hanoi.

Police suggested they waited until the entire identification process was complete before releasing details of those who died.

"Our priority has been to identify the victims, to preserve the dignity of those who have died and to support the victims' friends and families," said Assistant Chief Constable Tim Smith.

"It remained of paramount importance to us to ensure that an individual's next of kin were informed, and that they were given some time to absorb this tragic news before we publicly confirmed their loved one's identity."