AUSTIN, Texas (AP/CBSDFW) – Police in central Texas say synthetic marijuana that caused more than 30 people to fall ill was obtained in Dallas and sold by dealers in downtown Austin.

Austin police said Friday they haven’t been able to obtain a sample of the so-called K2 synthetic drug. They say it’s designed to mimic the high caused by using marijuana.

READ MORE: 'I'm Worried I'm Going To Kill My Parents' Man Told 911, Pointed Fake Gun At Fort Worth Police Before Being Killed

The Austin American-Statesman reports at least 37 people became ill in about a week.

Authorities seized about 360 packets of other brands of K2 from the three people they say sold the drugs in Austin. But testing showed that the components used to make the drug are not illegal and no charges were filed.

In Dallas, police reported over 120 overdoses since May 1st.

Investigators say those who used the K2 first became catatonic and then turned aggressive when they regained their senses

READ MORE: Dallas City Council Unanimously Approves Major Ethics Reforms

(©2014 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

Latest News:

[display-posts category=”news,sports” wrapper=”ul” posts_per_page=”5″]

Top Trending:

MORE NEWS: Harris County Jail, Texas' Largest, Under Renewed Scrutiny After Report Of Sexual Assault Of Sergeant