Eighteen people have been arrested on drug charges at a NYCHA housing development in Brooklyn.

It follows a 16-month investigation at the Sheepshead-Nostrand Houses by the Department of Investigation, FBI and NYPD.

Fifteen alleged members of the Towaz Boyz Gang are facing drug and conspiracy charges.

The other three people arrested are NYCHA employees.

Two allegedly bought marijuana at the complex while on duty and in uniform. The third is Shakina Rowe, a NYCHA caretaker who allegedly unlocked an apartment after a court-ordered eviction and allowed people back inside to do their drug sales.

The Department of Investigation says NYCHA knew these people had been engaged in this kind of activity.

"NYCHA once again, despite the fact we have pointed this out to them several times, NYCHA again failed to take steps to get people that they knew were engaged in illegal and dangerous activity out of NYCHA housing," said Mark Peters, commissioner of the Department of Investigation.

"By and large, they are good people. But supervision is poor," said Jimmy Fant, a NYCHA tenant. "I have to say it like it is. Supervision is poor."

NYCHA released a statement, saying, "We have no tolerance for illicit activity in public housing. While this is an ongoing investigation, we applaud the diligent work of our partners to help improve safety and security at NYCHA."

The three arrested employees were suspended.