Boeing is hiring new workers to replace employees in its defense unit as their strike enters a second month without a new contract agreement.

“Unfortunately, the union continues to demand more of everything while also saying it has no control over what it will take to end the strike, driving the parties further apart,” said Dan Gillian, a vice president at Boeing and senior executive at the St. Louis site, where many of the defense workers are located, in an emailed statement. “As a result, we’re taking the next step in our contingency plan and hiring permanent replacement workers for manufacturing roles to ensure we’re properly staffed to keep supporting our customers.”

Boeing didn’t say how many workers it’s hiring. The workers assemble and maintain F-15 fighter jets as well as missile systems.

“Boeing is doubling down on its mismanagement by saying it plans to hire replacement workers to build military aircraft and equipment, instead of negotiating with their dedicated, generational and skilled workforce,” IAM Union International President Brian Bryant said in a statement. “Boeing – let’s get back to the negotiating table. Let’s get real about the concerns of our members and your employees.”

The 3,200 workers, represented by International Association of Machinists and Aerospace Workers District 837, went on strike on Aug. 4 after turning down a contract offer from Boeing.

The company had offered a 20% general wage increase, a $5,000 ratification bonus and other improvements. Boeing said the increases could average about 40% taking into account other improvements. The increases would bring average IAM 837 machinist pay to more than $102,000 from $75,000, according to a note from Jefferies last month.

Boeing’s defense unit contributed about 30% of the company’s $42 billion in revenue in the first half of this year.

The strike comes less than a year after more than 32,000 unionized machinists who build commercial aircraft walked off the job after failed contract talks last year.

Their seven-week strike hobbled the company’s aircraft output and ended after they voted to approve a contract with 38% raises over four years and other improvements, marking the latest in a series of aviation labor unions winning higher pay as the industry faces a shortfall of trained workers.