A former US intelligence officer has appeared in court in Seattle charged with attempting to spy for China.

Ron Rockwell Hansen, 58, was arrested by the FBI on Saturday on his way to a Seattle airport for a flight to China, BBC reported on Tuesday.

The justice department says Hansen attempted to pass on information and received at least $800,000 for acting as a Chinese agent.

He agreed in a brief court appearance to be returned to his home state of Utah to face charges.

Hansen, who lives in Syracuse, Utah, was charged with attempting to gather or deliver national defence information to aid a foreign government.

Other charges – there are 15 in total – include acting as an unregistered foreign agent for China, bulk cash smuggling, structuring monetary transactions and smuggling goods from the US.

If convicted of attempted espionage, Hansen faces a maximum penalty of life in prison.

Assistant Attorney General John Demers called Hansen’s alleged actions “a betrayal of our nation’s security” and an “affront to his former intelligence community colleagues”.

John Huber, US attorney for the state of Utah, called the allegations “very troubling”.

According to court documents cited by the justice department, Hansen served in the US Army as a warrant officer with a background in signals intelligence and human intelligence, before being recruited by the Defense Intelligence Agency (DIA) as a civilian intelligence case officer in 2006.

The justice department says Hansen, who is fluent in Mandarin and Russian, held top secret clearance “for many years” and travelled regularly between the US and China in 2013-17.

He is alleged to have attempted repeatedly to regain access to classified information after he stopped working for the US government, thereby alerting authorities to his actions.

The Defense Intelligence Agency is a branch of the Department of Defense, responsible for analysing and disseminating military intelligence.