NEW HAVEN, Conn. (AP) — Connecticut authorities say a person possibly seeking to steal an air conditioner broke into a hospital’s nuclear medicine lab, triggering a hazmat response to a possible spill of a radioactive substance.

New Haven Assistant Fire Chief Mark Vendetto said Saturday there was no release of radio-isotope at the former St. Raphael’s Hospital, which is now part of Yale New Haven Hospital. Officials had said earlier some employees were exposed to radioactive material.

Authorities say a security worker reported a “compromised window” around 8 a.m. Fire officials say employees found that an air conditioning unit had been removed and the room ransacked.

The report led to a full hazmat response. Officials say about a dozen employees were screened for radioactive exposure.

Vendetto says there was no contamination.

A message was left at the hospital.

Copyright 2017 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.