PALO PINTO COUNTY (CBSDFW.COM) — Officials with the Brazos River Authority say first responders and emergency personnel are on a recovery mission for two people in the Brazos River, near the Possum Kingdom Lake Dam.

According to the game warden, everything started around 9:30 p.m. Thursday when three teenagers from Fort Worth — all believed to be 19-years-old —  were in the dam spillway area fishing.

Officials say one valve of the dam was open and the teens somehow got swept away by the current.

One of those boys was able to make it to a shoreline, but lost his clothes in the process. The two other teen went under and haven’t been seen since.

(credit: Chopper 11)

From the air, Chopper 11 could see a base set up by rescuers.

There are a pair of dive teams working to find the teens and for the first time ever an underwater drone is being used in the search. Officials say the mechanical water device is about the size of a large remote controlled car.

“The big boulders at the bottom makes it difficult and time consuming to work that grid pattern. It’s a slow methodical process, that we have some other agencies coming in to assist Texas Parks and Wildlife with this grid search down below the dam,” Michael Foster with the Texas Game Warden said.

According to the Game Warden, the area is a popular spot for fishing but that the three teenagers had crossed into a restricted area.

The teen who made it to shore only had minor injuries and did not require hospitalization.