Investing.com -- Google pulled out of a $100 million Pentagon competition to develop voice-controlled autonomous drone swarm technology after its proposal was accepted, Bloomberg reported Tuesday.

The company informed the government on Feb. 11 that it would not continue participating in the initiative, which aims to create technology for controlling drone swarms. The withdrawal came weeks after Google submitted its proposal. Records reviewed by Bloomberg News indicate the decision followed an internal ethics review, though Alphabet Inc.'s Google officially cited insufficient resourcing as the reason for its exit.

The same records show that several Google employees working on the project were disappointed by the withdrawal decision. The extent to which Google's initial entry was known across the company remains unclear. Hundreds of Google's AI researchers have previously objected to the company's advanced technology being used for classified military projects.

The Pentagon program is jointly led by Special Operations Command's Defense Autonomous Warfare Group and the Defense Innovation Unit. The initiative envisions commanders directing drone swarms by converting voice commands such as "left" into digital instructions.