A second boy has died after a group of children were shocked by an electrical current as they swam at a marina in a Tennessee lake.

Grainger County Sheriff Scott Layell said 11-year-old Nate Lynam of Morristown was pronounced dead at 7:35 p.m. Thursday at East Tennessee Children's Hospital, NBC station WBIR reported.

Another boy, Noah Winstead, 10, of Morristown died Wednesday at the German Creek Marina on Cherokee Lake in Bean Station, WBIR reported. 

Officials said the two boys and an 8-year-old girl were swimming between two houseboats when they were shocked. The adults and a 12-year-old boy were shocked when they tried to get the three children out of the water. The two children who survived were siblings of the boys who died, officials said.

Grieving father fights invisible killer of swimmers 

"At first, everybody thought maybe they were being stung or snake-bitten and everyone began to jump in to attempt to save them," said Layell.  "When they hit the water, of course, they became [victims of electric shock] as well and paralyzed for some period of time.  So many people coming to the rescue, jumping in, risking their lives, not knowing what they're getting into; that's just pure heroism.  That's what true heroes are made of."

The incident was one of two on the Fourth of July involving deaths of children who were shocked while swimming. In Missouri, 13-year-old Alexandra Anderson and her 8-year-old brother,  Brayden, were killed when they were shocked around noon by an unknown source of electricity while swimming near a private dock in the Lake of the Ozarks, KSHB-TV reported. 

Read the full report at WBIR

Nate Lynam's family released the following statement after his death:

The family of Nate Lynam is overwhelmed by the outpouring of love, prayers, and support from family, friends, and the community.

It is the family's wish that the tragedy that claimed his life not be what defines it. Nate was a loving son, a loyal brother, and a kind and respectful young man.

If there is anything newsworthy in this tragedy it is this: Nate and his friend, Noah, loved Jesus and trusted in Him. The family finds great comfort in knowing that they will be reunited one day in Heaven.  

The First Baptist Church in Morristown, Tenn.,  has set up the Fund for Our Two Families to provide financial support for the victims' relatives, WBIR reported. Donations may be sent to the First Baptist Church; P.O. Box 1899; Morristown, TN 37816.  The church finance director said a method to donate online is being established.

Saul Young / AP

Evidence tape covers an electrical meter near two houseboats at German Creek Marina in Bean Station, Tenn., on Wednesday after a fatal accident involving electricity and swimming.

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