A fourth person has been detained in connection with a narcotics investigation that netted three arrests last week, according to the Aiken County Sheriff’s Office.

Terra Nicole Allen, 29, of Graniteville, was charged with possession with intent to distribute LSD, possession of heroin, unlawful prescription of a prescription drug, trafficking LSD and unlawful neglect of a child. She was placed in the Aiken County detention center, where she remained on Monday afternoon.

Cheryl Wright, Russell Whitt and Adam Sloan were arrested following a traffic stop on May 14 while investigators were patrolling the Oxford Trace neighborhood doing follow-ups on drug activity complaints, police have said.

After searching the vehicle, police arrested and charged Whitt and Wright, who were in the vehicle, with trafficking heroin. Investigators then obtained a search warrant for 1321 Oxpen Court, where an illegal clandestine lab was discovered, leading to the arrest of Sloan, police have said.

Sloan was charged with trafficking heroin, trafficking LSD, possession of a firearm with an obliterated serial number, possession of a sawed-off shotgun and possession of a firearm during the commission of a violent crime. He remained in the detention center on Monday afternoon.

The investigation is ongoing, and it is unknown if additional arrests will be made, according to Capt. Eric Abdullah, a spokesman for the Sheriff’s Office.

• Teddy Kulmala covers the crime beat for the Aiken Standard and has been with the newspaper since August 2012. He is a native of Williston and majored in communication studies at Clemson University.