Law enforcement officials announced an indictment Wednesday against 29 suspected members of the "Mac Balla Bloods" who police say smuggled weapons into Rikers Island, such as scalpels and razor blades.

The yearlong undercover probe used wiretapping and police surveillance to take down the suspected gang members. Police say the street gang is the based in the South Bronx.

The alleged gang members are named in seven separate indictments that include robbery, burglary, criminal possession of a weapon, weapons charges and attempted murder.  

The attempted murder charge stems from a planned gang killing that was about to be carried out in June. Authorities say they were able to thwart the attempt.

Fourteen suspected Mac Balla members were recently arrested. Police are searching for six others. Authorities say nine alleged members were already incarcerated.

Investigators say the razors blades were confiscated before they got into the hands of inmates.