Canadian Forces Sub-Lt. Jeffrey Paul Delisle walked into the Russian Embassy in Ottawa in 2007 and offered to sell secrets to that country's military intelligence agency, beginning an espionage career that lasted almost four years, according to court details revealed by CBC News after the naval officer pleaded guilty to spying.

Delisle, 41, pleaded guilty in a Halifax court Wednesday to breach of trust and two counts of passing information to a foreign entity between July 2007 and Jan. 13, 2011, in Ottawa and Kingston, Ont., and Halifax and Bedford, N.S., where he lived.

• Jeffrey Delisle: What's known about the naval officer turned spy

According to previously unpublished material from a bail hearing, Delisle walked into the embassy wearing a red ball cap and civilian clothes. He flashed his Canadian military identification and asked to meet with someone from GRU, the Russian military intelligence.

Delisle was posted to the security unit HMCS Trinity, an intelligence facility at the naval dockyard in Halifax. It tracks vessels entering and exiting Canadian waters via satellites, drones and underwater devices.

While there he worked on a system called the Stone Ghost, said CBC reporter Rob Gordon.

"It's a computer system that links the five eyes. The five eyes are the United States, Britain, Australia, New Zealand and Canada. All their information is shared on the Stone Ghost computer.

"He would go to work every time with a thumb drive and download reams of information, which he would then send to the Russians on a monthly basis. This went on for years and years and years."

He was paid between $2,800 and $3,000 a month for the information.

In 2009, when Delisle wanted to stop dealing with the Russians, they sent him a picture of his daughter walking to school in Halifax.

Sub-Lt. Jeffrey Paul Delisle covers his face leaving a Halifax court Wednesday where he pleaded guilty to breach of trust and two counts of passing information. (Steven Puddicombe/CBC)

Shortly thereafter, the navy officer was told to meet his GRU handler in Brazil.

The Russians told Delisle they wanted him to be a pigeon, a spy term for a person who deals with all the secret operatives in an area. In this case it was Canada.

Delisle agreed and was handed $50,000 in cash. But when he couldn't get the money through Canadian security, the GRU gave him $40,000 in pre-paid credit cards and $10,000 in cash.

When he landed at the Halifax airport, customs agents wanted to know why he was in Brazil, why he only spent a few days there and why he had thousands of dollars in cash.

Delisle told him he was on vacation, that he only spent a few days there because he didn't have much time and that he always liked to travel with cash.

Guards allowed him to enter Canada, but were suspicious and notified the military that they suspected some kind of wrongdoing.

It was then the military and RCMP began an investigation, which resulted in a raid on Delisle's house in December 2011.

Preliminary hearing cut short

Delisle's preliminary hearing was scheduled to start Wednesday morning, but the lawyer told the judge his client would plead guilty to all three charges.

The judge asked Delisle, "Do you understand the charges?" and he nodded yes, reported the CBC's Stephen Puddicombe.

He wore the same grey-blue hoodie and jeans he has worn to all his court appearances since his arrest.

After Delisle entered his plea, it was determined that his sentencing hearing will be Jan. 10 and 11.

He's the first Canadian to face charges under the country's Security of Information Act.

That act lays out an array of breaches, ranging from threatening the safety of the Forces to selling software and the technical details of operations.

The Criminal Code charge can net a five-year prison sentence, and convictions under the Security of Information Act can lead to life in prison.

Delisle was posted to the security unit HMCS Trinity, a multinational base with access to secret data from NATO countries.