Authorities in St. Bernard Parish arrested six people last week following a drug bust that led to the seizure of more than a half-pound of heroin, Sheriff James Pohlmann said Monday.

It was likely the largest heroin bust in his three decades with the Sheriff’s Office, Pohlmann said. In all, 8.3 ounces of the drug were confiscated, carrying an estimated street value of $100,000, he said.

Deputies also confiscated $29,000 in cash, 11 grams of marijuana and the painkiller tramadol, authorities said.

Six people, including a 15-year-old, were arrested.

Pohlmann said the group’s ringleader was Alvin Clay, 28, who moved to the 3700 block of Shangri-La Drive in Chalmette in January.

Authorities said the heroin was found in a safe at Clay’s home.

When he was arrested, Clay already was out on bond in Orleans Parish after recent busts for possession with intent to distribute heroin and marijuana, Pohlmann said.

Clay was booked at the St. Bernard jail on counts of possession with intent to distribute heroin, possession of up to 400 grams of heroin and possession of marijuana and tramadol. He was being held Monday on $250,000 bail.

Shonika White, 36, who was identified by authorities as Clay’s girlfriend, was booked on possession with intent to distribute marijuana and tramadol. Her bail was set at $7,500.

Three Chalmette men — Dorian Charles, 19; Keith Payton, 18; and Jimmy White, 24 — and the 15-year-old all were booked on possession of marijuana.

Maj. Chad Clark, commander of the Special Investigations Division of the Sheriff’s Office, said St. Bernard authorities seized a total of about 6.5 ounces of heroin last year on 47 arrests — an amount surpassed in one day by last week’s bust.

Law enforcement agencies across the country are battling a surge in heroin usage. St. Bernard authorities said they believe the drugs confiscated last week may have come to the area by way of Houston.

Pohlmann said the bust netted about “8,000 doses of heroin that people could’ve shot up that was taken off the street.”

“He’s only 28 years old, but he’s been in the criminal field for a long time,” Pohlmann said about Clay. “Now, with these pending charges against him both in New Orleans and here in St. Bernard Parish, it’s likely that he will spend a long time in jail from this point on.”

Follow Richard Thompson on Twitter, @rthompsonMSY.