Prosecutors say 'ongoing investigation has revealed new information', without providing additional detailUS prosecutors have dropped charges against a Mississippi man accused of sending ricin-laced letters to Barack Obama and a US senator, according to a court order signed by a judge on Tuesday.The move came hours after Paul Kevin Curtis was released from a Mississippi jail on bond.In a court order calling for the charges to be dismissed, prosecutors said the "ongoing investigation has revealed new information" without providing any additional detail.An FBI agent had testified in court that no evidence of ricin was found at Curtis's home.Meanwhile, authorities searched the home of another Mississippi man on Tuesday in connection with the case.More soon …US national securityUnited StatesFBIMississippiBarack Obamaguardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies.