Washington (CNN) Seven US service members died in four noncombat-related air crashes in just four days, prompting concern over readiness in the US military.

The chairman of the House Armed Services Committee, Mac Thornberry, R-Texas, released a statement Saturday saying the "readiness of the military is at a crisis point."

The incidents coincided with President Donald Trump's decision to deploy up to four thousand National Guard troops to several Southwestern states. The Pentagon has been working with state and federal agencies on the logistics to execute the President's stated goal.

However, with few specifics coming from the administration, defense officials have been left to grapple with questions on how the military plans to balance its priorities -- a challenge that is only amplified by the fact that 16 US service members have been killed in noncombat aircraft crashes in recent weeks.

"Last month Congress voted to provide our troops the funds they need to begin turning this crisis around," Thornberry said in his statement. "That vote involved painful choices, but Congress was right to make it and the President was right to sign it into law. Given the urgency and importance of this issue, there can be no higher priority for the Department of Defense than ensuring that our aircraft are safe and that pilots get the training they need. Nothing should divert us from that mission."

On Thursday, a day after Trump ordered National Guard troops to the border , Pentagon spokesperson Dana White discussed the readiness issue.

"Border security is national security, and we are leaning forward to support the President and his intent and his goals," White said. "But readiness remains our top priority."

"The secretary believes that this needs to be the most lethal force in the world. ... So, yes, I can assure you that our resources will still be dedicated to ensuring that our war fighters get what they need when they need it," she said.

Not a crisis?

The US military maintains that it is not experiencing an aviation "crisis" despite a string of noncombat incidents that have killed 16 service members since mid-March, but lawmakers on both sides of the aisle warn that the recent spate of deadly mishaps is part of a disturbing trend that has been building for years.

Three of last week's incidents occurred on Tuesday and involved Marine Corps aircraft -- including a CH-53 helicopter that crashed near Naval Air Facility El Centro in California and killed four crew members.

An Air Force Thunderbirds pilot was also killed when his F-16 jet crashed at Nellis Air Force Base in Nevada on Wednesday. Two soldiers were killed in an Army AH-64E Apache helicopter crash at the local training area of their base in Fort Campbell, Kentucky, Friday night.

When asked if the recent incidents indicate a crisis, Joint Staff Director Lt. Gen. Kenneth McKenzie said Thursday that he is not prepared to characterize the mishaps as evidence of a "wave" or "crisis."

But McKenzie acknowledged that any deadly incident is "not normal" and each crash will be thoroughly investigated.

"We look for causality," he said. "Was it a single incident? Was it systemic? Is it related to something we're doing across the entire fleet ... or something in the training of the aviators that are flying the platforms? Or is it a maintenance issue?"

"We work very hard to uncover all those things, to look both individually at each accident, each mishap, as well as linkages between the two," he added.

Where will the money come from?

In 2017, four times as many US troops were killed in accidents than in combat -- a key point highlighted by many lawmakers and military officials who argued for additional defense spending to help offset readiness issues that have compounded for years.

While Trump approved what his administration calls the largest defense budget in US history last month, his unexpected push to use US military resources for immigration enforcement is raising concerns that the Pentagon divert some of its funding from other areas.

"Spending defense dollars to score political points means that there's less money for rebuilding readiness after 15 years of war," Arizona Democrat Rep. Ruben Gallego told CNN. "That's why it's shameful that President Trump wants to waste DOD resources on a pointless parade and a National Guard deployment to the border."

"As a veteran, I'd much rather see the more than $100 million that it could cost to send troops to the border go instead to ensuring that our men and women in uniform have the training and equipment they need to remain the world's preeminent fighting force," said Gallego, a member of the House Armed Services Committee.

Thornberry also recently cautioned against diverting resources from the military and has long expressed concerns about the lasting impact that years of budget cuts will have on readiness.

But Thornberry has not openly criticized the President's plan to deploy National Guard troops as the details of the plan are being worked out.

"We don't know enough about the size, scope or duration of this deployment to say if it poses a risk to recovery," a congressional aide told CNN when asked about the effect the deployment could have on readiness.

Asked about contrasting military readiness with sending National Guard troops to the border in an interview with Fox News, Arizona Republican Rep. Martha McSally, an Air Force veteran, said "we need to do both, and we can't afford not to secure our border."

"If you look at these National Guard troops, citizen soldiers ... a lot of them are in support areas. They can support intelligence, their main career field, supporting fleet management to free up border patrol agents to patrol on the border. It is doing both," she added.