The federal government is stepping in to stop the flow of synthetic marijuana.

Emergency officials announced that a new federal law requires postal inspectors to track all pharmaceutical shipments from overseas.

The move comes after more than 100 people overdosed on the New Haven Green almost two months ago. Officials believe the drug behind the overdoses may have arrived in the U.S. mail from other countries.

"They can pretend to be legal pharmaceuticals, but if the source is known, then the postal officials and the customs police can crack down on them," says Sen. Richard Blumenthal.

The new laws are part of an opioid bill Congress passed that gave Connecticut $30 million to help fight the opioid crisis.

New Haven authorities say that the new law isn't about reacting to overdoses, but preventing them.

"We're still learning," says Rick Fontana, the head of the New Haven Emergency Management.

As part of the deal, the federal government will also be giving Connecticut 10,000 Narcan kits for police and fire departments across the state.