"There is an obligation here, especially considering there are a lot of rumors going around," college professor Brian Woodworth, a Republican, said Thursday. "There's an obligation they have to let people know what's going on. There's still an air of mystery."
Postal worker Marcus Lewis, who is challenging Jackson as an independent, agreed. He said the lack of details about Jackson's illness only contributed to the rumors, and he questioned the timing of Jackson's announcement last week, which came just before the deadline for independent and new party candidates to file candidacy papers.
"Because you are a public servant, tell us the facility or the treatment center where you are. Don't go under the ground," he said. "You need to let your constituents know where you are. This is getting ridiculous."
Jackson spokesman Rick Bryant has said that Nayak's arrest had nothing to do with the medical leave and that Jackson's congressional offices remain open.
The congressman has kept medical information under wraps before. He underwent weight loss surgery in 2005, but he disclosed it months later after questions were asked about a nearly 50-pound weight loss.
Jackson represents Illinois' 2nd District, which traditionally includes neighborhoods on Chicago's South Side and in its south suburbs. The district was expanded this year to include more territory south of the metropolitan area that isn't as familiar with him.
Reaction in Jackson's district, where voters have overwhelmingly supported him each election, was a mix between people wanting to know more and wanting to respect the congressman's privacy.
"I want to be fair, but we find out he's ill so soon after his friend was charged," said Frances West, 74, who was at a local post office. "I said, 'That sure does sound strange.' At the same time he's been under a lot of stress (for years) as a congressman."
Ann Baker, 60, who was eating lunch at a restaurant frequented by Jackson — a calendar with his picture hangs on the wall — said it was a personal matter.
"He's done a great job for us for so long," she said. "But people speculate. We all do it. Nine out of 10 times there's nothing behind it. We're getting enough information. He's human and we all have problems."
Associated Press Writers Don Babwin in Chicago and Henry Jackson in Washington contributed to this report.
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