Detective Sgt. John Arahovites said police have noticed an increase in the number of Maine-registered cars driving in the Lake Street, Crystal Street, Jericho Road and Broadway areas during the day, when most neighbors are at work.
He said drug customers and their dealers arrange the meetings in the "secluded, affluent" area of the city over their cell phones, then meet at a prearranged location to buy drugs. The drug dealers sometimes come from outside Haverhill, police said.
More than 20 drug arrests have been made in the area during the past two years, Arahovites said. Those arrested were mostly for heroin and some for cocaine, he said.
"We have a lot of heroin up there," Arahovites said.
Arahovites said police often receive calls from concerned business owners and residents along the Route 97 corridor when the callers spot suspicious activities, which include Maine-registered cars waiting in parking lots with the occupants clustered around a pay phone.
"We have a rapport with several people in the area, and when they see that kind of activity they call us directly," Arahovites said.
"The Maine plates are a red flag," Arahovites said. "We are seeing a lot of them."
The stretch of Route 97 is within two miles of Interstate 495.
The latest arrests happened Tuesday when Arahovites said he and Detective Gary Melanson, in separate unmarked cars, tried to pull over a car containing two men on Lake Street, but the car sped up and the detectives saw one of the men throw an object out the window. Melanson continued the pursuit and the car stopped a short distance away, Arahovites said.
Arahovites said he stopped and recovered the object thrown from the car - "a big ball of cocaine weighing 22.5 grams and worth an estimated $2,000."
Marco Delacruz, 52, 26 Eutaw St., Lawrence, was arrested and charged with trafficking cocaine, conspiracy to violate drug laws and driving after revocation of his license. Kelvis Nunez, 27, 101 Exchange St., Lawrence, also was arrested and charged with trafficking cocaine, conspiracy to violate drug laws, resisting arrest and distribution of cocaine, second offense, police said.