The arrest of two men suspected of manufacturing methamphetamine in a Perley Street duplex Friday is the second case involving the production of the illegal drug in Concord in as many weeks, police said.

“We’ve seen the prevalence of meth steadily increase,” Concord police Lt. Tim O’Malley said. “We’ve seen a lot of possession of meth, and also separate incidents where meth is involved.”

Concord isn’t alone.

After so many years in law enforcement, you begin to notice some trends in crime, Franklin police Chief David Goldstein said.

“There’s a cycle of drugs that can be substantiated through hard numbers,” he said. “There seems to be a constant search for something.”

Meth – and most illegal drugs – never really go away, Goldstein said.

“None of this stuff has ever left. It’s always in the background,” he said. “We’re still out here fighting a good fight.”

In recent years, more and more New Hampshire drug users seem to be choosing methamphetamines. According to data from Concord police, from 2012 to 2015, the annual number of arrests involving meth in the capital city rose from 15 to 107 – more than a 600 percent increase.

Data from 2016 show Concord to be on track for an even greater number of meth-related offenses – 58 were reported in the first four months of the year.

“I think if you would run our records from 10 years ago, you saw almost nothing,” O’Malley said.

O’Malley said most users obtain the illegal drug by purchasing it from out of state or manufacturing it themselves, often using a “single-pot” method to create small batches of the substance. The Perley Street case on Friday involved the latter.

Police found what appeared to be a meth lab in the basement of the building, and a state police clandestine lab expert later confirmed the report, according to court documents.

Following an anonymous tip, officers arrived at the gray duplex at 25 Perley St. to perform a welfare check on a 4-year-old child and follow up on previous tips about a meth lab. They arrested James Mott, 31, and Adam Roz, 41, both of whom had outstanding warrants on unrelated charges.

The child was brought to the hospital for a medical evaluation and then released. It took about seven hours for a responding team from the Drug Enforcement Agency to remove hazardous materials and search the premises. After that, O’Malley said residents would have been able to re-enter the building.

At least two other adults were at the scene Friday but not arrested. Officials sent evidence to a lab, O’Malley said, to determine if charges related to manufacturing meth will be brought forward.

Cases like this have not been all that uncommon, he added.

O’Malley referred to a case last fall when Concord police officers seized almost $40,000 in cash and more than 30 grams of methamphetamine from a Bow Street home after nearly a dozen people were arrested.

More recently, officers responded to calls from people who spotted 26-year-old Edward Hill throwing burning items out of the second-floor window of his South Main Street apartment. Hill was arrested June 16 and charged with manufacturing of methamphetamine and possession of Suboxone, both felonies.

Police have seen a number of cases where a person possessed both heroin and meth, O’Malley said. Though both are dangerous, he said, the chemicals involved in methamphetamine manufacturing pose an extra threat.

“They’re both bad,” he said. “They’re both very concerning. But the laboratory method adds an element of concern and fire hazards.”

Goldstein said from his experience, more people are using the “single pot” method to manufacture the drug in bottles and bags, increasing the risk of fires or explosions.

“Safety is always first and foremost. Don’t ever touch it,” he warned.

Six years ago, Franklin launched a task force to combat drug use throughout the community. The program focuses on prevention initiatives in local schools, Goldstein said.

“We’re trying to solve a problem before it becomes a problem,” he said.

It’s just one part of the push to ultimately reduce the number of cases involving methamphetamine and other drugs, Goldstein said. But despite police efforts, New Hampshire is in the throes of a drug crisis.

“And think of the reason why,” Goldstein said. “If we focus on a particular drug or class of drugs, why won’t they go on to something else?”

(Katie Galioto can be reached at 369-3302, kgalioto@cmonitor.com or on Twitter @katiegalioto.)