A U.S. judge ordered a Moroccan man to be held on charges that he planned a suicide bombing attack against the U.S. Congress, believing he was working with al Qaeda militants when in fact his contacts were undercover agents.
Amine El Khalifi, 29 and an illegal immigrant, was arrested last week and charged with attempting to use a weapon of mass destruction against U.S. government property, intending to detonate a bomb and to shoot people.

He was arrested just blocks from the U.S. Capitol and had been the subject of a lengthy undercover investigation by the FBI who said the public was never in danger because he was monitored and only given weapons that were inoperable, Reuters reports.

El Khalifi popped up on law enforcement authorities' radar in January 2011 when a confidential source told authorities that he met with others in Virginia and agreed with statements that the group needed to be ready for war, according to court documents.

A law enforcement agent went undercover posing as a member of an armed extremist group and met with him in December 2011 where they discussed various plots to attack U.S. military offices, an Army general, a Jewish synagogue and a Washington, D.C. restaurant, according to an FBI affidavit filed in court.

In January, El Khalifi switched his planned target to the U.S. Capitol. He detonated a test bomb just over a month ago in a quarry in West Virginia and he "expressed a desire for a larger explosion in his attack" at the Capitol, the FBI said.

The arrest and charges are the latest in a string of undercover operations by the Obama administration. U.S. officials have become increasingly concerned about individuals launching attacks within the United States.

According to court records, El Khalifi entered the United States in 1999 on a visa, overstayed it and never applied for U.S. citizenship. That has prompted criticism from lawmakers about the ability of visitors to overstay visas and not get caught.

El Khalifi, wearing a green prison jumpsuit, waived his right to a detention hearing. Judge John Anderson said the suspect's immigration status and the charges against him warrant his remaining in custody. The hearing lasted just a few minutes.

The case is next expected to be presented to a grand jury, which will consider whether there is enough evidence to bring him to trial.