AUSTIN, Texas - After a three month investigation, Austin police say 36 people are facing charges for buying and selling the K2.

In a joint effort involving Austin police, EMS and FBI undercover officers have made ten new arrests while charging a total of 36 people.

Each day officers respond to around 10 calls involving reactions to K2, especially near the Arch - Austin's downtown homeless shelter.

It's a difficult situation for officers because K2 is made by using any number of chemicals, so arrests can only be made after lab tests.

These chemicals are bought internationally, making distributors hard to track down.

Officials say it's been a years-long, exhaustive investigation and it's not over yet. They hope to update the community again soon with international agents at their side.