ANAHUAC, Texas – New human remains were found at the crash site of the Amazon Prime air cargo jet that crashed Saturday.
Crews continue to search for the plane's black boxes, a key to determining what may have caused the crash.
The recovery mission has been very challenging with Tuesday’s bad weather and the very thick mud in Trinity Bay. Chambers County Sheriff Brian C. Hawthorne said a K-9 found the remains around 2 p.m. but the body has not been recovered.
"We will not stop looking for the third body until we have that third body recovered," Hawthorne said.
Investigators said their priority at this point is recovering evidence, which includes large pieces of debris from the water, to have it cleaned up and examined. Investigators said all four points of the plane have been located. They hope the black boxes may be inside.
WATCH: Chambers County Sheriff, FBI give update on plane crash
"Quicksand is a very good description of how it is. When you step off you can easily go 1 to 2 feet very quickly and there's things inside and underneath that you can't see as you can imagine, there's potentially sharp objects under there so it can be a potentially hazardous situation," FBI Assistant Agent in Charge Ed Michel said.
Authorities are using cadaver dogs to search on land, and KPRC2 has seen airboats in the water, which is littered with wreckage.
Investigators said the plane encountered rough weather before it went down, breaking into pieces and killing the three people on board.
Some of the search crews are equipped with monitoring devices to capture "pings" from the 767's flight data recorder and cockpit voice recorder, but as of Monday, they had not heard anything.
"The mud could play a part with the signal and the acquisition of the signal itself," Michel said.
A source identified the victims as Capt. Ricky Blakely, Capt. Sean Archuleta and Officer Conrad Aska.
Wreaths were placed near a staging area in their honor. The FBI says the victims' family members are scheduled to visit the site Tuesday, but they will not speak publicly.
The Red Cross has been helping the families.
Meanwhile, investigators are preparing to remove the debris from the water.
"They're just now starting to unload the equipment. They're starting to pick up some of the debris, which is on the surface. After they get what's on the surface, they'll start raking before they'll start dredging," Hawthorne said.
The process could take weeks. FBI agents said the investigation could last another two to four weeks. The general lifespan of a black box is 30 to 60 days.