Iran has proven far better prepared for armed confrontation than officials in the White House had anticipated, The New York Times reports, citing representatives of the U.S. military command.

According to the sources, the scale of losses recorded during the first week of fighting reflects that level of preparedness. Since the start of the military operation, Iranian retaliatory strikes have claimed 20 lives, and casualties have also been reported among U.S. troops.

Military officials also point out that Tehran’s current tactics differ markedly from its previous approach. In the past, Iran often issued advance warnings about planned strikes and indicated potential targets. The latest attacks, however, have become broader in scope and far less predictable.

The U. S. Central Command (CENTCOM) reports that eight American service members have been killed as part of the operation known as Epic Fury. U. S. President Donald Trump has already acknowledged that the number of casualties among American troops could rise.

The joint military campaign by the United States and Israel against Iran began on February 28. In response, Tehran has been launching missile and drone strikes targeting Israeli territory as well as U.S. bases located in Persian Gulf countries.