Members of the Puerto Rico National Guard patrol a highway flooded by Hurricane Maria. (Photo by Sgt. Jose Ahiram Diaz-Ramos/Puerto Rico National Guard)

The Pentagon will expand its response to the devastation in Puerto Rico left by Hurricane Maria, deploying a one-star Army general along with more aircraft, a hospital ship and a variety of specialized units all focused on surging relief efforts.

The moves followed a visit by Federal Emergency Management Agency Director William “Brock” Long, and after the U.S. military re-opened two major airfields capable of handling the Pentagon’s massive cargo jets. Army Brig. Gen. Richard C. Kim, the deputy commanding general of U.S. Army North, will coordinate operations and make sense of what more is needed, defense officials said.

People in Puerto Rico have been desperate for more help, and many have criticized the federal government’s decision making. Pentagon officials have defended the military’s response, however, saying it has supplied everything FEMA has requested while preparing for a long-term recovery effort.

Combined, there are currently about 5,000 active-duty U.S. service members and National Guardsmen on duty assisting Puerto Rico, including more than a thousand who work from the USS Kearsarge and USS Oak Hill, ships deployed off the coast of Puerto Rico, said Army Lt. Col. Jamie Davis, a Pentagon spokesman. Far more were involved in the recent responses to Hurricane Irma and Hurricane Harvey.

Elaine Duke, the acting secretary of Homeland Security, called the deployment of the general a “big step forward,” telling Senate lawmakers Wednesday that his presence will help accelerate decision-making on the ground.

The U.S. military also has opened a former base, Naval Station Roosevelt Roads, on the eastern side of the island. The flight line there can accommodate military jets, freeing the Luis Muñoz Marín Airport near San Juan to accept commercial flights to and from the U.S. mainland. That airport was opened by the U.S. Army Corps of Engineers on Friday, and has seen a fleet of incoming military jets since carrying supplies.

“What DOD is doing is helping us get the supplies there, but also helping us open the access roads,” Duke said, referring to the Defense Department. “They also are leading the debris removal, which is huge. We still have areas that we can access by roads.”

U.S. Northern Command, which oversees operations in Puerto Rico, said in a statement Wednesday afternoon that a massive C-5 cargo jet arrived in Puerto Rico on Wednesday carrying about 50 people and equipment needed to set up a headquarters on land.

Marines and sailors have been transporting first responders and fuel and performing route clearance, the statement said. They also are transporting Health and Human Services assessments teams to hospitals across the island to determine what medical needs there are.

One C-17 jet and two C-130s also arrive in Puerto Rico with an assessment team from the Federal Aviation Administration. They are working to bring airfields back to full operations.

Air Force Gen. Lori Robinson, who oversees the military response as chief of U.S. Northern Command, said at an event in Washington that even more units and equipment will arrive in the next day or two.

“You have to understand what is happening on the ground so you don’t add to the burden, but to make sure you put the right capability and capacity,” she said. “So, whether it’s power generators or whether it’s water and food, those are things that we already have been shipping in.”

The Pentagon’s remains smaller than relief operations marshaled after other major natural disasters, including Hurricane Katrina in 2005 and a 2013 typhoon that devastated the Philippines. In those cases, the military established a joint task force led by a three-star general. Critics of the response to Maria, including Rep. Adam Smith (D.-Wash.), the ranking member of the House Armed Services Committee, has called for the Pentagon to do so in Puerto Rico, too.

Asked what additional needs there might be, Robinson said, “We haven’t caught our breath yet,” and that the military intends to determine what lessons should be learned from Hurricane Maria.

“For me personally, do we have the right faces in the right places in the right spaces and the command from a staff perspective?” Robinson said. “Did we look at having the right capability and capacity at the right place. To me, that’s a lesson learned thing, and definitely something I want to turn around and look back at, because I think there will be some things that we are able to learn.”