CHICAGO (CBS) — Authorities arrested the man they believe to be the “Swine Flu Bandit” outside a South Loop bank Wednesday, as the alleged serial robber was allegedly planning his tenth heist.

Matthew D. Mahoney, 28, was charged with one count of armed bank robbery, a felony, in a complaint filed Thursday in U.S. District Court, according to a release from the Chicago FBI office.

Mahoney, of Chicago, is suspected of robbing four banks since last Thursday, and other before that. He was allegedly planning a tenth robbery when officials arrested him Wednesday outside a First American Bank at 1241 S. Wabash St., officials said.

Members of the Chicago FBI’s Violent Crimes Task Force were inside the bank, which Mahoney is suspected of robbing in September, when they noticed a man matching a description of the Swine Flu Bandit — and wearing the same clothes worn during robberies earlier this week — standing outside, the release said.

Officials claim he was planning his tenth robbery at the time of his arrest and found a 9 mm semi-automatic handgun in his coat pocket, the release said. He was arrested without incident.

The complaint charges Mahoney with only the Nov. 6 robbery of a Chase Bank branch at 550 S. Dearborn St., in which he escaped with more than $55,000, the release said. However, he is suspected in eight additional robberies committed by the “Swine Flu Bandit,” including seven more in Chicago, one in Oak Lawn and one in northwest Indiana.

The most recent robberies were at Chase bank branches, a release from the FBI office said. At 9 a.m. Monday, he is believed to have robbed the branch at 1130 W. Taylor St. and at noon struck the branch at 4809 S. Ashland Ave.

He earned the moniker because he wore surgical masks in earlier thefts and told at least two suspicious bank employees who confronted him that he was recovering from the swine flu, the FBI said.

Judge Jeffrey T. Gilbert ordered Mahoney held without bond in a Thursday hearing, the release said. He will be held in the Metropolitan Correctional Center in Chicago until his next court date on Nov. 16 and faces up to 20 years in prison if convicted of the charge.

Chicago FBI’s Violent Crimes Task Force, which includes FBI special agents, Chicago Police detectives and Cook County Sheriff’s office investigators, investigated the case.

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