The ground search for a missing pilot from a downed Air National Guard jet resumed Thursday morning with more than 100 trained rescue personnel and volunteers combing the densely wooded area near the Virginia and West Virginia border.

“This is still a search and rescue operation,” Major Matthew Mutti, 104th Fighter Wing public affairs officer, told TheBlaze. “The focus is still on rescuing the pilot, and we are hopeful that he is OK.”

F 15 Crash Update: This is Still a Search and Rescue Operation

A Virginia State Police search helicopter hovers close to the scene where an Air Force F-15C fighter jet based in Massachusetts crashed near Deerfield, Va., Wednesday, Aug. 27, 2014. The jet was on a standard training exercise to receive a system upgrade and had no munition onboard, said Maj. Matthew Mutti, from Barnes Air National Guard Base. Officials said the pilot’s status is unknown. (AP Photo/The Staunton News Leader, Griffin Moores)

Radio contact with the pilot was lost Wednesday at approximately 9 a.m., and the F-15C Eagle, assigned to Massachusetts’ 104th Fighter Wing, crashed approximately five minutes later near Deerfield, Virginia.

Search and rescue crews from the Virginia State Police and the Virginia National Guard immediately responded to the incident, and a U.S. Customs and Border Patrol helicopter that was airborne at the time of the crash for a different mission diverted to the area to assist in the search within minutes of the crash, Virginia State Police representative Corinne Geller said.

“The dense foliage adds to the challenge,” Geller told TheBlaze, “but that’s also why we had aviation assets up immediately to assist in the search.”

Though witnesses reported seeing a potential ejection and a descending parachute prior to the crash, Mutti said the search teams could not substantiate those claims and are not working with any firm leads based on those reports.

If the pilot did safely eject, it is also unclear whether the seat transmitters are functioning properly; asked if the search teams were tracking an emergency signal from the ejection seat, Mutti said, “not that I can report.”

Seven helicopters have rotated in and out of the operation since the units were notified of the crash, and the air assets continued their search well into the night after the ground search efforts were suspended at midnight to prevent injuries to the volunteers in and around the “dangerous terrain” around the crash site.

“An AC-130 was introduced at roughly 3 a.m. with its robust sensors to try and find the pilot,” Mutti said. The HC-130 is assigned to Moody Air Force Base and has specialized equipment designed for low-light/night-time search and rescue operations.

Another volunteer flight crew member for Department of Homeland Security search and rescue missions confirmed to TheBlaze they also contributed assets to the search.

“As of last night an S-76 and up to two A-star’s, equipped with TRAKKA pods and night sun search lights, went over yesterday and to my knowledge are still down there,” the volunteer told TheBlaze.

The Massachusetts Air Guard sent additional personnel to the crash sight late Wednesday night to coordinate with the Virginia Department of Emergency Management on the search efforts.

“We sent down security forces members as well as some technical advisors, one pilot and another person who can advise on the hazards of the F-15 … it carries fuels and other things that local officials wouldn’t be familiar in dealing with,” Mutti said.

U.S. Air National Guard Col. James Keefe, commander of the 104th Fighter Wing, takes questions from reporters in front of Barnes Air National Guard Base, in Westfield, Mass., Wednesday, Aug. 27, 2014, about a crashed Massachusetts Air National Guard F-15C fighter. An experienced pilot on a standard maintenance mission was missing Wednesday after his fighter jet crashed in the mountains of western Virginia. (AP Photo/Steven Senne) AP Photo/Steven Senne

U.S. Air National Guard Col. James Keefe, commander of the 104th Fighter Wing, takes questions from reporters in front of Barnes Air National Guard Base, in Westfield, Mass., Wednesday, Aug. 27, 2014, about a crashed Massachusetts Air National Guard F-15C fighter. (AP Photo/Steven Senne)

Geller said that as of Wednesday morning, the military official has the lead in the search, though Mutti said the effort is still a jointly led operation, and both representatives said the communication hurdles caused by the heavily wooded and very hilly terrain are causing some problems.

“Right now it’s a combination of both the state police and one of our pilots, Lt. Col. Andrew Jacob, is serving as the on-scene commander, but it’s a multi-faceted effort, so there are many people helping coordinate the efforts right now,” Mutti told TheBlaze.

Before the crash, the pilot, whom Mutti described as “experienced,” departed from Barnes Air National Guard Base in Westfield, Massachusetts, on a mission to deliver the F-15C to a joint Naval Air Station and Reserve Air Base in New Orleans so the aircraft could receive radar upgrades.

UPDATE, 1:25 p.m.

104th Fighter Wing Public Affairs released an update to TheBlaze, stating search efforts are centered around the southeast side of Mount Crawford, Va., near the Washington National Forest.  Rescue efforts include more than 9 aircraft, including the specially equipped HC-130, and the wing now has 16 members on site assisting in securing the site and coordinating the rescue operations.

“There continues to be more than 100 state police, sheriff’s deputies and fire and rescue personnel on scene.   Approximately 10 search-and-rescue teams are on the ground searching along logging roads, fire trails and forest roads,” the release states.

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