Joint Base Lewis-McChord, Washington (CNN) -- For three weeks, security fears kept U.S. authorities from searching the Afghan village where an American soldier is accused of killing 16 Afghans, an Army investigator testified Wednesday. Local tempers were so high over the killings that it was too dangerous for the Americans to go, said Matthew Hoffman, a special agent with the Army Criminal Investigation Command. Negotiations with local leaders over the issue took 20 days -- and even then, the investigators were guarded by U.S. and Afghan troops and watched over by two U.S. helicopters, he said. "We were fully expecting to be attacked at any time," Hoffman said. "We didn't know how much time we had for our investigation."
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Army Sgt. Robert Bales is accused of killing 16 Afghan villagers
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It took nearly three weeks for U.S. agents to visit the site, an Army investigator says
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"We were fully expecting to be attacked at any time," he says
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Another investigator testified that steroids were found outside Bales' quarters
His team collected blood samples, took photographs and found a number of 9mm shells at the site, but much of the evidence had been collected by @placeholder troops the day after the March 11 killings, he said.