LAFAYETTE, Colo. -- Immigration officials and members of a criminal investigative arm within the Defense Department helped execute a search warrant at an optics company Thursday.

Friday the company issued a statement that said:

"On the morning of October 11, Federal Authorities began an on-site investigation of Rocky Mountain Instruments procedures. The company is fully cooperating with the investigation. No accusations or arrests have been made, and the company is back in operation today. It is our understanding that this investigation is not related to terrorism, immigration or hazardous materials. Also. Our affiliate company, RMI Laser is not under investigation."

With a convoy of about 50 cars, members of Immigration and Customs Enforcement, the Defense Criminal Investigative Service (DCIS) and Lafayette police surrounded Rocky Mountain Instrument Company.

Immigration and Customs Enforcement spokesman Carl Rusnok confirmed ICE agents and the DCIS participated in the search of Rocky Mountain Instrument Co. He said he could not provide details since the investigation is ongoing.

The raid began around 9 a.m. Thursday morning, and agents were working into the evening talking boxes out of the business and loading them into a U-haul.

It was not immediately clear when the raid would be complete.

According to its Web site, DCIS is the criminal investigative arm of the inspector general of the Department of Defense investigating terrorism, product substitution, computer crimes, illegal technology transfers and public corruption.

The search warrant was sealed. There was no danger to area residents, said Jeff Dorschner, a spokesman for the U.S. Attorney's Office.

Rocky Mountain Instrument Co., located on Laser Drive, provides electro-optical systems, optics, coatings and assemblies, according to its Web site.

A company representative didn't return a phone message seeking comment.

Curt Ripplinger, an insurance broker who works next door, saw agents enter the building.

"We saw the ICE people and the police when we came to work this morning at 9," said Ripplinger. "What they are looking for is a curiosity to me."

Ripplinger said several of his clients work at Rocky Mountain Instrument Co. and said some of the workers are very educated Koreans or Russians--all speak English.

According to the Daily Camera, agents filed into the business' front door about 9:30 a.m. and firefighters clad in fluorescent vests and helmets filed into the building about one hour later.

The operation seems to be a slow-going investigation that's being kept fairly low-key, but a DCIS agent was evacuated at one point and taken to Exempla Good Samaritan Hospital. The man was alert, but wearing an oxygen mask.

Sources tell 7NEWS the agent may have suffered from an allergic reaction to something inside the building requiring he be taken to the hospital.

The source said the agent was exposed to a substance that one would expect to find at a company like this.

The agent is doing OK, the source said.

Nearby businesses and roads are being kept open during the operation, and abutting stores have been notified about the operation.

Rocky Mountain Instrument Co. is a 50-year-old company that does a lot of business with the federal government and the military building lasers used in laser-guided bombs and the optics in the new F-22 fighter jet.

The company has also done business with foreign governments.