4 children among those killed in massive fire that destroyed 35 boats at Alabama dock

Four children were among the eight people killed when a massive fire swept through an Alabama marina and destroyed 35 boats, some being used as permanent residences, authorities said on Tuesday.

The ages of the children who perished in Monday morning's blaze in Scottsboro were 7, 9, 10 and 16, Jackson County Medical Examiner John Jordan told ABC News.

Jordan said all of the victims have been identified, but he is not yet prepared to release the names of those who died.

While the search for additional victims is ongoing, Scottsboro Fire Chief Gene Nicklaus told ABC News that "we believe that we have all the souls accounted for."

Nicklaus said at a news conference on Tuesday that an investigation into the cause of the fire has been launched by the Alabama fire marshal. He said the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, the National Transportation Safety Board and the U.S. Coast Guard are also investigating the incident.

He said some of the investigators working to find the cause of the tragedy also probed a fire on Sept. 2 that killed 34 people on a 75-foot dive boat anchored off Santa Cruz Island in Southern California.

The ferocious blaze on Monday broke out around 12:40 a.m. at a marina at Jackson County Park on the Tennessee River and rapidly spread, Nicklaus said.

In addition to the eight bodies recovered from the water, seven other people were injured and taken to area hospitals, Nicklaus said. He said the injuries were minor.

"This kind of loss on any scale is huge, but for a small community it's incredibly tragic and rough," Nicklaus told ABC News.

He said the 35 vessels that burned ranged from 20-foot pontoons to 40-foot houseboats that up to 21 people were using as their permanent residences. It remained unclear how many people were on the boats and the dock when the fire broke out.

"That proved difficult because of the nature of people coming and going off of houseboats and not knowing how many people were staying with who," Nicklaus said.

Video footage showed a long dock with flames shooting from what appeared to be a row of houseboats.

Nicklaus said when firefighters arrived, 30% of the dock was engulfed in flames. He said firefighters initially confronted "substantial access problems" in reaching people trapped by the flames.

Some people escaped the fire by jumping into the frigid water, he said, and some boats sank at the dock while others broke from their moorings and sank in the lake.

Nicklaus said that 17 different agencies, including the Jackson County Sheriff's Office and neighboring fire departments, responded to the scene.