Federal agents stumbled onto one of the largest drug labs they’d ever seen when executing four search warrants last week in Southern California.

The FBI found more than 2,000 kilograms, or more than 4,400 pounds, of “pill product” that could be made into illegal drugs at a drug lab in the Orange County community of Garden Grove, Laura Eimiller, a spokeswoman for the bureaus’ Los Angeles field office told Los Angeles Times reported.

Eimiller said agents also found what they believe to be counterfeit Xanax pills, methamphetamine and bath salts in the lab.

No arrests were made Tuesday. It was not immediately clear whether there were people inside the lab when the FBI raided them.

Federal agents also descended on locations in Irvine and two other unidentified spots, said Eimiller.

Before the Irvine raid, FBI agents had to evacuate nearby residents as a precaution prior to executing the search warrant, she said.