FORT LAUDERDALE, Fla. — Looking frail and meek, Esteban Santiago, the man accused of fatally shooting five people and wounding six others at the airport in this South Florida city three days ago, made a brief appearance on Monday in a federal courtroom here and was assigned a public defender because he cannot afford a lawyer.

Shackled, bearded and wearing a red jumpsuit, Mr. Santiago, 26, an Iraq war veteran who grew up in Puerto Rico, took several deep breaths and jiggled his legs nervously as he waited for the judge. Federal marshals towered over him when he stood.

Speaking with a slight Spanish accent, Mr. Santiago told Magistrate Judge Alicia O. Valle that he had $5 or $10 in his checking account, owned no property and had not held a job since November. That was the same month that he walked into an F.B.I. office in Alaska carrying an ammunition clip — leaving a pistol and his infant son in his car — to complain about a C.I.A. plot against him. F.B.I. agents called the local police, who took him to a psychiatric center where he spent a few days.

Before November, Mr. Santiago said he had spent nearly three years working security for Signal 88 in Anchorage, Alaska, where he earned $2,100 a month. He also spent about 10 years in the Army, where he earned $15,000 a year in his last three years of service.