(Reuters) - Opengate Capital Group LLC filed a lawsuit on Friday alleging that laboratory equipment maker Thermo Fisher Scientific Inc <TMO.N> sold it a Mexican plant last year without revealing that a drug cartel was operating there.
The private equity firm claimed that the Reynosa, Mexico-based manufacturing facility, which it acquired as part of a larger deal from Thermo Fisher, had been regularly infiltrated by gangs from the Gulf Cartel since at least 2011, according to a copy of the complaint seen by Reuters.
The lawsuit, filed in federal court in Los Angeles, alleged that Thermo Fisher had acted in bad faith by withholding documents and directing employees to conceal the drug gang's presence at the facility.
Opengate said gang members brandished weapons to intimidate employees at the facility and parked their cars and "tractor-trailers filled with unknown cargo" there.
It also said employees sought help from Thermo Fisher to address the cartel activity, but that security upgrade proposals were not implemented.
"Thermo Fisher made none of the upgrades that were recommended by its security advisers in January and February 2012, and took no meaningful action to fortify or further secure the Facility in response to the continuing cartel infiltration," the complaint said.
The suit claimed that Thermo Fisher had rushed negotiations and provided misleading answers to due-diligence inquiries.
Opengate did not specify what damages it was seeking.
Thermo Fisher, the world's largest maker of laboratory equipment and scientific instruments, agreed to acquire Life Technologies Inc <LIFE.O> in mid-April for more than $13 billion.
Thermo Fisher was not immediately available for comment outside of normal U.S. business hours.
The company's shares closed at $84.46 on Friday on the Nasdaq.
(Reporting by Pallavi Ail in Bangalore, Karl Plume in Chicago; editing by Gunna Dickson)