The Bears weren't able to add help at defensive tackle during the draft, so they found some on the street.
An NFL source told the Tribune the team agreed to terms Thursday night with John McCargo, a former first-round draft pick of the Bills, and DeMario Pressley, former teammates at North Carolina State. Both players will receive one-year contracts.
Henry Melton, Matt Toeaina and Stephen Paea, last year's second-round draft pick.
The Buccaneers released McCargo this month. The Bills drafted him 26th overall in 2006, and his most productive season was 2007, when he played in all 16 games and made 29 tackles with 2 1/2 sacks. The 6-foot-2, 307-pounder appeared in four games for the Bucs last season.
Pressley was a fifth-round pick of the Saints in 2008 and played in seven games in their 2009 Super Bowl season. He has been with the Colts, Broncos and appeared in one game last season with the Panthers.
McCargo and Pressley were part of a tryout Thursday at Halas Hall that also included defensive tackle Trey Lewis and defensive end Cheta Ozougwu, sources said.