The underground units often engaged in regular battles with the Soviets and their Polish clients (see: Battle of Kuryłówka).

Mr. Phuoc, who came from a wealthy Saigon family, was an 18-year-old student and part of a 17-member underground unit in 1968.

In general, underground units remained calm.

The Dutch resistance ranked among the most dedicated and disciplined underground units in all of occupied Europe.

Late in 1940 he went to Paris, where he served in an underground unit by working as a street and cafe portrait artist.

The underground units have clocked solar winds and monitored even the slightest coronal flares.

Behind him was a map purporting to show similar underground units around the nation.

A great deal of effort went into putting up shelters in underground units, even in old transport tubes and the like.

Vital records, which she said were much more important, are usually stored in underground units that are more secure and more expensive.