Two Illinois Congressmen are calling for public hearings into the mail bombs sent from Yemen addressed to Chicago synagogues. Jan Schakowsky and Jesse Jackson Jr. want congressional hearings on the mail bomb plot. In particular, what role Chicago plays in the investigation.

U.S. officials have said al-Qaida intended the mail bombs to detonate before they reached their Chicago destinations. But they were intercepted first.

Department of Homeland Security Secretary Janet Napolitano wouldn’t give any clues as to Chicago’s role in a phone interview with WBEZ last week. “That’s a question I have, I’m sure Chicagoans have is: Why were they addressed in Chicago? And the investigation is ongoing,” Napolitano said.

Meantime, authorities say they’ve stepped up cargo screening efforts at U.S. airports.