Abu Khalid Abdul-Latif, also known as Joseph Anthony Davis, of Seattle, and Walli Mujahidh, also known as Frederick Domingue Jr., of Los Angeles, were arrested Wednesday night after they arrived at a warehouse garage to pick up machine guns to use in the attack, an FBI agent wrote in a criminal complaint filed in U.S. District Court.

The machine guns had been rendered inoperable by federal agents and posed no risk to the public.

The men were scheduled to make initial court appearances Thursday on terrorism and firearms charges. It was not immediately clear if they had obtained attorneys. They could life in prison if convicted.

The Homeland Security Department said in a May 31 assessment with other organizations that it did not think it likely there would be coordinated terrorist attacks against military recruiting and National Guard facilities.

The agencies agreed, however, that lone offenders or groups would continue to try to launch attacks against these facilities.

"Our review of attempted attacks during the past two years suggests that lone offenders currently present the greatest threat," according to the assessment, marked "for official use only" and obtained by The Associated Press.

Recently, terror supporters have encouraged their followers to focus on simple attacks and not complex, elaborate ones like those on Sept. 11, 2001.

"Unlike hardened facilities such as active duty military bases and installations, soft targets such as recruiting stations are more likely to be deemed a feasible target due to their easy, open access to the public," the assessment said.

The agencies also predicted that successful, non-elaborate attacks overseas, such as those where crude car bombs were used, could inspire similar tactics in the U.S.

Authorities learned of the Seattle plot early this month when a third person recruited to participate alerted the Seattle Police Department, the complaint said. Investigators immediately began monitoring the men, and the confidential informant continued to string them along by promising to obtain weapons.

The building, the Military Entrance Processing Station on East Marginal Way in Seattle, also houses a daycare. Recruits for all military branches are screened and processed there.

In audio and video recordings, the men discussed the plot at length, discussing how to time their attack at military recruits, such as by tossing grenades in the cafeteria, the complaint said.

"The key thing to remember here is, is we are not targeting anybody innocent — that means old people, women out of uniform, any children," Abdul-Latif is quoted as saying. "Just people who wear the green for the kaffir Army, that’s who we’re going after."

The agent wrote that they also fantasized about the headlines the attack would generate — "Three Muslim Males Walk Into MEPS Building, Seattle, Washington, And Gun Down Everybody" — and speculated that if they got control of the building, television news crews would arrive to cover them.

Mujahidh, 32, voluntarily spoke with investigators after the arrests and confessed, the complaint said.

"Mujahidh admitted that he was planning on carrying out an attack at the MEPS for the purpose of killing United States military personnel in order to prevent them from going to Islamic lands and killing Muslims," the complaint said.

Abdul-Latif, 33, and Mujahidh, 32, are charged by complaint with conspiracy to murder officers and employees of the United States, conspiracy to use a weapon of mass destruction, and possession of firearms in furtherance of crimes of violence. Abdul-Latif is also charged with two counts of illegal possession of firearms.

The U.S. Attorney’s Office in Seattle said the defendants initially planned to attack Joint Base Lewis-McChord but later changed targets. The defendants intended to carry out their attack with both grenades and machine guns, the government said.

"The complaint alleges these men intended to carry out a deadly attack against our military where they should be most safe, here at home," Seattle U.S. Attorney Jenny A. Durkan said in a statement. "This is a sobering reminder of our need to be vigilant."

Abdul-Latif has previous felony convictions for first-degree robbery and custodial assault, as well as misdemeanor convictions for obstructing a law enforcement officer, assault and theft.

When he was prosecuted on the robbery charge in Kitsap County, Wash., in 2002, Abdul-Latif was ordered to undergo a psychological evaluation, and despite some "issues" was found competent to participate in his defense, the FBI agent wrote.

Abdul-Latif was sentenced to 31 months in prison on that charge.

Mujahidh does not appear to have a criminal record, the agent wrote.

In a bankruptcy filing from a month ago, Abdul-Latif reported assets of about $3,000 and liabilities of about $6,000. He reported that about $2,000 in monthly income from a janitorial business was entirely nullified by the expenses of operating Fresh and Clean Janitorial. His wife, identified as Binta Moussa, was earning about $1,200 a month, according to court documents but that wasn’t enough to cover their costs of living.

Steve Dashiak, a bankruptcy attorney representing Abdul-Latif, told The Associated Press he was stunned by the developments, and that his client seemed like a regular man.

"I sensed no ill will from him whatsoever," Dashiak said. "He seemed like a guy just trying to make it, having a rough time because business wasn’t going very well. To say that I didn’t see this coming would be an understatement."

Potential recruits came and left as normal at the military processing center Thursday. Children and adults were having a barbecue behind a fence at the same building.

Army Corps of Engineers Col. Anthony Wright, commander of the Seattle district and senior official for the building, said he was kept informed about the threat and made some changes in security as a precaution.

"I’ve spent about three years in Iraq. It’s a little different to feel it here in Seattle, but it’s part of the world we live in," he said.

The two-story building is a former Ford factory from the 1930s converted into offices. The 600 Corps of Engineers employees make up about two-thirds of the people in the building.

The corps held its annual picnic Thursday in an outside portion of the complex. Wright said they decided not to cancel after hearing the good news of the arrests.