Charles Foehner, the elderly man who kept a arsenal of guns inside his Queens apartment, remained jailed after a Friday court hearing where authorities detailed his confession to fatally shooting an ex-con during a botched robbery.

Foehner had told authorities he was carrying a weapon over fears of street crime exacerbated by the oft-criticized changes in New York bail laws, a police source told the News.

“I pulled a gun out of my pocket,” prosecutors quoted Foehner as saying once in custody after the fatal Wednesday night showdow.

“It didn’t go off accidentally. I pulled the trigger. I emptied the revolver.”

The defendant, now facing weapons possession charges for the 25 guns recovered from his apartment after the shooting, was held on $50,000 cash bail or a $100,000 bond.

“My office is charging Charles Foehner with multiple counts of criminal possession of a weapon,” said Queens District Attorney Melinda Katz in a statement. “These are the charges factually supported by the evidence.”

In the showdown, Cody Gonazlez waved a sharp object — later determined to be a pen — after approaching the victim, authorities said.

Foehner was walking up a driveway leading to an entrance to his apartment building on 82nd Ave. near Queens Boulevard in Kew Gardens when the mugger confronted him around 2 a.m., cops said.

The crook demanded the gunman’s cash and cigarettes.

As the robber approached, Foehner flashed a revolver but Gonzalez continued to advance. Foehner then shot the suspect in the chest, according to the NYPD.

The defendant fired five bullets and called 911 after the shooting.

“I really don’t know much, to tell you the truth,” his weeping wife said outside the courtroom. “I’m sorry ... “I just know that he’s a really good guy, but that’s all I’m going to say.”

In an exclusive interview with the News, Gonzalez’s family said their slain relative was mentally disturbed and that his intended victim shouldn’t be blamed for defending himself.

“We don’t fault the shooter,” said Stephan Gonzalez, 35, who is related to slain crook Cody Gonzalez’s adopted family by marriage and has known him for more than 12 years.

Foehner was ordered by Queens Criminal Court Judge Jerry Iannece to return for a Monday court date.