(NewsNation) — A cold case involving a missing person led divers in Florida to discover dozens of cars submerged in a lake near Miami.

Volunteer divers with a United Search Corps, which works to try to solve missing persons cases that have gone cold, searched the murky waters of a lake in Doral, Florida, finding dozens of cars. The group works all over the state, using sonar and divers to search bodies of water for cars.

Volunteer divers estimated around 30 cars, while the Miami-Dade Police Department put the estimate at 20, but said it will be impossible to have a full count until all cars have been recovered.

The lake is located in a commercial area, and United Search Corps founder Doug Bishop told 7News they believed the cars had been dumped in the lake as part of criminal activity.

“This many in one lake is pretty alarming,” Bishop told NewsNation.

The Miami-Dade Police Department began recovery efforts Tuesday. Due to the conditions in the water, including poor visibility and currents that may have moved vehicles away from the shore, Miami-Dade Police Department Public Information Officer Alvaro Zabaleta said the operation will take some time. Some cars may have to be pulled by boat through the water until they are in range of cranes and tow trucks.

Zabaleta said the first car removed, a 2002 Altima, was confirmed stolen by the Doral Police Department. He said they expect the majority of the cars to be connected to crimes such as theft or fraud, rather than more serious crimes.

However, Zabaleta said the homicide unit was standing by in the event any of the vehicles turned out to be connected to a homicide or death investigation.

Bishop said he doesn’t believe they found a car connected to the case they were working on.

“A lot of these vehicles are very old,” he said.

However, there are missing persons cases that have been ongoing for decades,