Hundreds of Boeing engineering employees could be laid off in June, according a letter from Boeing Vice President of Engineering John Hamilton.

Hundreds of engineering employees and managers accepted voluntary layoff offers in January and March, according to Hamilton. However, the company says hundreds of other will likely be cut on an involuntary basis in Washington and at other unspecified places around the country.

“Even with this amount of employment activity, we need to reduce our employment level further in order to meet our operating plan and additional challenges in the marketplace,” Hamilton wrote in the letter.

Boeing has cut 1,332 engineering and technical jobs in Washington since January, according to SPEEA. Another 300 workers took voluntary buyouts.

Additional layoffs later this year will be “driven by our business environment” and how many people leave voluntarily, Hamilton wrote.

The 60-day warning notices are expected to go out Friday. The layoffs are planned for June 23.