UPDATE: NYC Landlords Handed Cash to Undercover Inspector: Prosecutors

About a dozen New York City building inspectors are expected to be arrested on corruption-related charges Tuesday, NBC 4 New York has learned.

Law enforcement sources say the investigation focuses in part on improper payments made to inspectors at construction sites to avoid violations. More than a dozen contractors and others are also expected to be charged in connection with the probe.

Officials would not disclose the specific nature of the alleged payoffs or how much money was involved. They did not identify any of the individuals expected to be arrested.

The arrests are expected to be announced by the Manhattan District Attorney, the Department of Investigation Commissioner and NYPD officials. More than 100 law enforcement officers will take part in processing the more than two dozen people who are expected to be charged.

A spokeswoman for the Manhattan district attorney's office declined comment, saying only news briefing was scheduled for 12 p.m. Tuesday. An NYPD spokesman referred calls to DOI, a spokeswoman for which declined to comment on the expected charges.

The Department of Buildings did not immediately return a request for comment.

Past law enforcement investigations in 2009 and 2012 resulted in arrests of building inspectors. Officials alleged some contractors in those sweeps had ties to organized crime.