Denver ? A group of suspected drug users arrested in Denver this weekend with methamphetamine, guns and bulletproof vests made racist threats against Barack Obama but posed no true danger to the presidential candidate as he accepts the Democratic nomination here this week, federal authorities said Tuesday.

The three men – all said to be high on methamphetamine when arrested – are the subject of an assassination investigation, but so far, authorities say, it appears they had no capacity to carry out any attack on Obama.

“The law recognizes a difference between a true threat – one that can be carried out – and the reported racist rantings of a drug addict,” U.S. Attorney Troy Eid said.

He said the men’s plans were “more aspirational, perhaps, than operational.”

The three have been charged with drug and weapons offenses but not with threatening to assassinate Obama.