A federal prosecutor Tuesday afternoon began outlining the case against a Lawrence man charged with threatening to blow up a school building.

Threats were made last April with a cell phone that police found in Michael E. Parker’s apartment at 12th and New York streets, assistant U.S. attorney David Smith said during opening statments in Parker’s federal trial in Kansas city, Kan.

Police used cell-phone tracing technology in locating the phone and detective work linking it to Parker, Smith said. But Parker’s defense attorney Jeffrey Morris said there was no evidence that Parker made the threats. Several people – who were using drugs – had entered and left the apartment during the hours leading up the phone calls, Morris said.

Police said nine calls were made from the cell phone to 911 between 5:15 a.m. and 8:09 a.m. on April 19. In some of those, threats were made.

Parker is on trial in front of U.S. District Judge Kathryn Vratil. The trial, which got under way today, is expected to last through the week.