Image copyright AP Image caption Authorities say Mr Booker attempted to attack Fort Riley in Kansas

A 20-year-old US citizen has been charged with attempting to explode a car bomb at Fort Riley in Manhattan, Kansas.

John T Booker Jr was making final preparations to carry out the suicide attack on behalf of the Islamic State (IS), the FBI said.

Mr Booker previously had tried to join the Army, but was denied entry because of internet posts about "jihad".

Authorities say that US personnel were never in danger.

He is the latest American to be arrested for attempted support of IS. Two Chicago men were arrested in late March for attempting to provide material support to the organization.

Earlier this month two women in New York City were arrested on suspicion of planning to use a weapon of mass destruction.

Booker, also known as Mohammed Abdullah Hassan, enlisted in the military "with the intent to commit an insider attack against American soldiers," according to the FBI complaint.

He had "formulated several plans for committing jihad once enlisted", including shooting soldiers on the firing range and kidnapping a high-ranking officer.

Image copyright Getty Images Image caption The FBI said Mr Brooker wanted to emulate Major Nidal Hasan (above) who killed 13 people in 2009

He told an undercover FBI informant that he wanted to show that "we will be coming after American soldiers in the streets... we will be picking them off one by one."

By 20 March 2014 he was told that he would not be permitted to join the military, and was questioned by FBI agents regarding Facebook posts declaring his sympathies for Islamic militants. He told the agents that he had "enlisted in the United States Army with the intent to commit an insider attack like Major Nidal Hasan."

Hasan, an army psychiatrist, opened fire inside Fort Hood, Texas, killing 13 people in 2009.

As a high school student Booker was quoted in a 2011 article in the Topeka Capital-Journal newspaper during a holiday event wrapping gifts for for US soldiers. "I can't have a good Christmas if they don't," Booker said in the story.

Jihad as 'adrenaline rush'

During his time as an army recruit he publicly posted to Facebook: "I'm going to wage jihad and hopes that i die," and "Getting ready to be killed in jihad is a HUGE adrenaline rush!!" He had been scheduled to begin basic training in less than one month.

After being denied entry to the military, the FBI said that he and an undercover agent formulated a plan to build and detonate a truck bomb at Fort Riley, which is a base near his home in Topeka, Kansas.

In early March 2015, Mr Booker and an FBI informant travelled to Freedom Park near Fort Riley to film a martyrdom video, according to the FBI complaint.

The video begins with Mr Booker, who was a military recruit at the time, proclaiming his loyalty to Abu Bakr al-Baghdadi, the leader of IS.

He has been charged with attempting to use a weapon of mass destruction, attempting to maliciously damage and destroy property of the US government, and attempting to provide material support to terrorists.