(KRON) — Federal agents seized a huge cache of GBL/GHB, also known as the “date rape drug,” that was mailed to a Fairfax salon, according to the Marin County Sheriff’s Office.

A San Francisco man who allegedly received the package at the nail salon was arrested by Homeland Security Investigations Division detectives. The package continued 3.5 kilos of the “date rape drug.”

Investigators said Long Tran was busted in an undercover operation. “With cooperation of the US Postal Service, a controlled delivery was performed at the nail salon,” MCSO wrote.

After Tran’s arrest, investigators said they found even more GBL/GHB inside Tran’s home.

In total, more than 3,500 doses of the drug — with an estimated street value of $20,000 — were seized, according to the Marin County Sheriff’s Office.

GHB is an illegal street drug that is sometimes sold at dance clubs and rave parties in a liquid form, the Drug Enforcement Administration wrote. The drug can cause the user to experience euphoria, drowsiness, confusion, and memory impairment.

The DAE wrote, “GHB and its analogues are also misused for their ability to increase libido, suggestibility, passivity, and to cause amnesia — traits that make victims vulnerable to sexual assault and other criminal acts.”