COBSCOOK BAY, Maine — Two “areas of interest” have been identified on the bottom of Cobscook Bay after federal scientists and state Department of Marine Resources experts spent three days this week exploring the seafloor with special sonar equipment.

All those involved in the search are hoping the sites hold some answers as to why Cobscook Bay has claimed so many commercial fishing vessels. Marine officials estimate a half-dozen boats have sunk in the bay in the last decade.

The sonar was being employed to find a possible obstruction — ledges or other protuberances — that could have hooked the boats’ gear and caused them to sink.

Two weeks ago, the Bottom Basher, a 34-foot sea urchin dragger, sank in 47-degree water with three fishermen on board. Searchers found the body of Darrel Cline, 41, of Lubec. The boat’s owner, Joseph Jones, 29, of Trescott, and Norman Johnson, 57, of Cutler remain missing.

In March, the fishing vessel All American also went down in Cobscook Bay, killing the captain, Loren Lank, 53, of Lubec, and deckhand Logan Preston, 19, of Roque Bluffs. Preston’s body also has not been found.

DMR Lt. Alan Talbot said Friday that DMR is planning a coordinated underwater dive to take a closer look at the two areas identified this week.

Everyone involved in the search as well as the communities affected by the sinkings are hoping the dive reveals the sunken boats. Talbot admitted there was a possibility that one or more of the missing fishermen’s bodies still could be trapped inside.

“We don’t know what is down there,” Talbot said. “We do know it is something unnatural, something we need to take another look at.”

The search team that has been working the bay with DMR this week is the National Oceanic and Atmospheric Administration’s Mobile Integrated Survey Team, or MIST. The team drove to Maine early this week with $1 million worth of specialized side-scan sonar equipment in a pickup truck.

Local officials and community members provided the four-man team with lodging, meals, boats and staff. At one point, four boats were participating in the sonar scan.

MIST’s portable sonar system most often is used to clear waterways after hurricanes and to create nautical charts. It shoots sound across a 120-meter path that is recorded on video and then reviewed later. If an object needs a closer look, the scan can be refined to 50 meters wide.

The first call for help was made last Thursday, and by Monday, arrangements for NOAA’s arrival in Eastport were under way.

“The combined cooperation here between all the agencies has been amazing,'' Capt. Robert Peacock said Wednesday. Peacock provided his boat, the Medric II, for use by the NOAA experts.

For three days, the team used the portable sonar scan to search the area near Falls Island and Leighton Point where debris from the Bottom Basher was found two weeks ago. The currents in that area are some of the strongest found anywhere, and both the tides and currents surprised the NOAA researchers.

“When we arrived, we went up to Reversing Falls and we got an education fast,” Lt. Commander Matthew Wingate of the NOAA team said earlier this week.

Talbot said dates for the dives have not yet been scheduled.

“We will have to coordinate the tides with the dive teams’ schedules,” he said. “We need the right tide in the middle of the day, so there is plenty of light.''

Talbot said the dive team could include DMR and Maine State Police personnel.