LAS VEGAS (AP) — A teenager arrested last week with an unloaded assault rifle at a Las Vegas high school has been linked by counterterrorism investigators to another local teen who federal authorities said stockpiled guns and explosives and spoke about staging a mass casualty attack.

Police already were looking for 18-year-old Jake Benton Howell when he arrived at his former school on Dec. 21 with 40 rounds of ammunition and a 7.62mm SKS rifle in the back seat of his car, according to a police report released Thursday.

Authorities had been checking reports that associates and friends of Steven Matthew Fernandes planned an action against the school, Northwest Career and Technical Academy, as revenge for Fernandes being held in federal custody, according to the police report.

Howell’s name was on a list that police and school officials compiled of current and former students with whom Fernandes associated at the 1,900-student campus.

Howell, now a student at Utah Valley University, was unarmed when he was confronted by a school police lieutenant. Police said he made no threats and caused no disturbance before his arrest. He told authorities he drove 400 miles from Orem, Utah, to visit favorite former teachers.

"Everything worked right," Clark County School District police Capt. Ken Young said Thursday. "We were looking into the rumors. Things came together and we were able to find a weapon at the school without an incident."

Howell later acknowledged his friendship with Fernandes, who he identified as the founder of a militia group called the 327th Recon Unit of Nevada. But he said he didn’t know of any plot against the school.

Investigators also found a compressed air pellet gun, camouflage backpacks and military-style uniforms, food, water and survival gear in Howell’s car. He told investigators he collected the items in anticipation of the collapse of society.

Howell was arrested on five charges of possession of a dangerous weapon on school grounds after police seized the gun and ammunition, a 16-inch bayonet and three large survival-style knives from the car. He was being held at the Clark County jail in Las Vegas pending a Jan. 8 court appearance.

Possession of a dangerous weapon on school grounds is a gross misdemeanor in Nevada that carries a possible penalty of a year in jail and a $2,000 fine.

The Las Vegas Review-Journal first reported the link between the two students.

Fernandes, also a former student at the high school, has been in federal custody since his arrest Sept. 13 driving to work at a RadioShack. Police found a loaded shotgun and ammunition in his car and reported seizing five rifles, four handguns and thousands of rounds of ammunition from his home, along with "The Anarchist’s Cookbook" how-to manual for manufacturing explosives.

Federal prosecutors have cited an email in which the 18-year-old Fernandes described himself as the commanding officer of 327th Nevada Militia, an urban survivalist unit with six or seven members. Authorities said he told a confidential FBI informant that he could kill more than the 12 slain in a theater last July in Aurora, Colo., that he would like to use children in a day care center for target practice and that he could attack the Las Vegas Strip.

He was indicted Sept. 25 on federal charges of possession of unregistered firearms, making firearms in violation of the National Firearms Act and transporting explosive materials. He has pleaded not guilty. Trial is scheduled in February.

Fernandes’ lawyer, Crystal Eller, said Thursday that the two teens were friends, but she hadn’t spoken with Fernandes about Howell and she didn’t know the extent of their relationship.

Eller characterized the militia group as "a small group of teenage boys camping, hiking, hanging out and playing Army, basically."

She acknowledged that the claims by federal prosecutors in her case sounded "scary," but that Fernandes hadn’t committed any crimes.

"We judge people based on what they do, not on what they say," the attorney said. "What has he actually done? He never hurt anybody."

Howell’s public defender, Dedree Smart Miles, declined to comment.

Las Vegas police didn’t immediately respond to questions about the investigation. Agent Patrick Turner, spokesman for the FBI office in Las Vegas, declined comment.