Military map symbol of a hostile unit or formation. The colour red has been used to distinguish hostile entities since the original APP-6 standard. In APP-6A the rectangular frame was replaced with a diamond frame for a more distinct hostile entity appearance even in black &amp; white.
<a href="//commons.wikimedia.org/wiki/User:CdnMCG" title="User:CdnMCG">CdnMCG</a>
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