SAN FRANCISCO (KRON) -- Two men accused of dealing a high volume of narcotics in San Francisco’s Tenderloin neighborhood were arrested Tuesday, the San Francisco Police Department announced. One of the two suspects, 24-year-old German Alfred Colindres Estrada of Oakland, was the subject of a four-month investigation conducted by the SFPD Narcotics Unit and the San Francisco Sheriff’s Office, police said, after being reported to be dealing "a high volume of narcotics in and around the Tenderloin neighborhood and the greater San Francisco area." Probable cause was developed in the case and a search warrant was obtained for Estrada, his residence and the vehicle he was utilizing. El Faro in SF Mission District hit with back-to-back break-ins Just before 11:30 p.m. on Tuesday, Estrada and 22-year-old Jose Colindres Erazo were observed by authorities parking the vehicle near 11th and Howard streets, SFPD said. Estrada and Erazo were detained by officers in the area of 11th and Mission streets. A K-9 at the scene alerted to the presence of illegal narcotics inside a backpack belonging to Estrada, police said. SFPD searched the vehicle and located a concealed loaded semi-automatic pistol. A search warrant executed at Estrada’s Oakland residence uncovered more than 1,330 grams of suspected fentanyl, methamphetamine, prescription pills and cocaine, SFPD said. Disassembled firearms and ammunition were found inside the residence. Also located were $45,000 in cash, a large hydraulic press, press plates and evidence of cutting agents to increase the volume of produced narcotics. Photo: San Francisco Police DepartmentPhoto: San Francisco Police Department Estrada was arrested and booked into San Francisco County Jail on charges of: Carrying a loaded firearm in a public place or vehicle Carrying a concealed firearm Prohibits convicted felons or persons with active felony warrants from owning purchasing, or possessing firearms 2 counts of possession for sale of a controlled substance Transporting a controlled substance Possession for sale or purchases for purposes of sale cocaine base Possession of methamphetamine for sale Criminal conspiracy Committing a felony while on bail or release Erazo was arrested and booked into San Francisco County jail on charges of: Carrying a loaded firearm in a public place or vehicle Carrying a concealed firearm 2 counts of possession for sale of a controlled substance Possession of methamphetamine for sale Possession for sale or purchases for purposes of sale cocaine base Transporting a controlled substance Criminal conspiracy Anyone with information in this case is asked to contact the San Francisco Police Department at (415)-575-4444 or text a tip to TIP411 and begin the message with SFPD. SFPD’s Tenderloin Plainclothes Unit, the San Francisco Sheriff’s Office, and special agents from the Drug Enforcement Administration assisted in the operation.