By Alex Millson

‘Plot to assassinate Barack Obama’ uncovered as police find weapons haul during routine traffic stop

Four people are have been arrested in connection with a possible plot to kill U.S. presidential candidate Barack Obama.

   Arrested: Nathan Johnson & Tharin Gartrell

One of the suspects told authorities they were ‘going to shoot Obama from a high vantage point using a rifle sighted at 750 yards’.

Police arrested 28-year-old Tharin Gartrell after he was spotted driving erratically near Denver, where Mr Obama is due to speak at the Democratic Party convention later today.

Officers recovered two high-powered rifles with scopes, camouflage clothing, walkie-talkies, wigs, a bulletproof vest, a spotting scope, licenses in the names of other people and 44 grams of the drug methamphetamine.

Police alerted federal officials because of heightened security surrounding the Democratic convention, Dudley said.

‘Clearly we found there are federal implications – otherwise we would not have notified them,’ Detective Marcus Dudley said. ‘The weapons clearly would cause great concern.’

Police went to a nearby hotel to contact an associate of Gartrell. But that man, identified as 33-year-old Shawn Robert Adolph, jumped out of a sixth floor window to escape detectives.

Adolph broke an ankle in the fall and was captured moments later.

Sources say he had a handcuff ring and was wearing a swastika, and is thought to have ties to white supremacist organisations.

A third man – an associate of Gartrell and Adolph – Nathan Johnson, 32, was also arrested. He told authorities that the two men ‘planned to kill Barack Obama at his acceptance speech’.

Johnson, along with his girlfriend, Natasha Gromek, are also under arrest on drug charges.

The Secret Service, FBI, ATF and the joint terrorism task force are all investigating the alleged plot.

The U.S. Attorneys Office has scheduled a news conference for later today. The U.S. Attorney in Denver said it does not believe there is a credible threat to Obama or the convention.

‘It’s premature to say that it was a valid threat or that these folks have the ability to carry it out,’ said a U.S. government official familiar with the investigation.

The official spoke on condition of anonymity because the investigation is ongoing.

U.S. Attorney Troy Eid said the case was under investigation.

‘We’re absolutely confident there is no credible threat to the candidate, the Democratic National Convention, or the people of Colorado,’ Mr Eid said in a prepared statement.