Less than four months after Tennessee Governor Bill Haslam signed the synthetic drugs bill, police say they’re making a comeback.

"It’s still not as bad as it was this time last year or even six months ago," said Leslie Earhart with the Sullivan County Sheriff’s Department.

According to the police records, there have been 13 reports involving synthetic drugs since June, including bath salts. "There have probably been many more cases where bath salts and synthetic drugs were suspected but the officers couldn't find proof,” she said.

At least four people have come in to the jail under the influence of synthetic drugs in the last two weeks, which is both dangerous and costly according to Earhart. "In one instance, a person was brought to the jail that was so high on synthetics they had to be transported to the hospital. Since they were in custody, it's a cost to taxpayers,” she said.

Now police and lawmakers are zoning in on the border. "Our vice detectives are investigating several cases involving people going to North Carolina, buying synthetics in bulk, bringing them back to Sullivan County and selling them here,” said Earhart.

Sullivan County District Attorney Barry Staubus said they were afraid that would happen after Tennessee passed their state-wide ban in May, following in Virginia’s footsteps. "When we passed this bill we knew it wouldn't be the end of synthetic drugs. We know when the law changes criminals change, so we have to adapt to what they do,” he said.

Staubus says he plans to work on the bill with legislators to broaden it so they can deal with these new situations. "It’s not unusual when a law is passed that there are exceptions and new developments that can't be anticipated so you go you go back and try to deal with these things,” he said.

Tennessee Representative Jon Lundberg, who worked on the synthetic drugs bill, said he is working with legislators in North Carolina to help them pass a comprehensive law. “If we can help North Carolina, we can also help Tennessee,” Lundberg said.