MARCUS HOOK, Pa. -- A seven-month investigation into a drug ring in Delaware County netted 14 arrests on Sunday night.

Undercover officers focused the investigation on Crest Tavern after receiving numerous complaints, authorities said.

“We’re not going to tolerate the drugs,” said Marcus Hook Mayor George McClure. “If you come to Hook looking for problems, you're going to get more than you can handle.”

Officers said some of the suspects wondered whether they were under surveillance.

“They were suspicious,” said Officer Daniel Rumaker, who participated in the investigation using the nickname Wolverine. “They thought I was a cop, but they still sold to me.”

Police said they made 46 drug purchases over seven months, including cocaine, marijuana and prescription drugs.

Police said the operation has netted 45 arrests since September.

The suspects will face stiffer penalties if convicted because the alleged crime occurred within a school zone. In Pennsylvania, there is a mandatory minimum sentence of two years in prison for this type of crime in a school zone, authorities said.

Police are still searching for seven suspects.