A traffic stop in Grover Beach led to an investigation and the arrests of four people on Thursday for alleged narcotics and weapons violations, the San Luis Obispo County Sheriff’s Office announced on Friday.

The 2:30 p.m. Tuesday traffic stop on Norma Lane off of Atlantic City Avenue and North Oak Park Boulevard led to someone being arrested on suspicion of having a stolen firearm and what authorities described as a large quantity of what the Grover Beach Police Department suspected was methamphetamine, according to a Sheriff’s Office press release.

That led to searches at a number of homes in Grover Beach after police brought in the Sheriff’s Office Special Operation and Narcotics units, as well as the San Luis Obispo County Gang Task Force.

Authorities say that more than 500 grams of meth were found, along with a stolen handgun, paraphernalia related to meth sales, evidence of a meth lab more than $3,500 of cash.

The Sheriff’s Office said those arrested were Joseph Anthony Amaya Jr., 19, of Bakersfield; Ramon Antonio Franco, 31, of Bakersfield; Roxanna Cristina Lopez, 35, of Grover Beach; and Juan Luis Lopez Quintana, 28, of Arroyo Grande.