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AUSTIN, Texas (FOX 7 Austin) - 25-year-old Martin Gutierrez was last seen leaving the Rainey Street bar district one night last November.
About a week later his body was found in Lady Bird Lake.
Martin's brother Mitchell is in the medical field. After seeing surveillance footage of his brother acting strangely before disappearing, he believes he was drugged.
"The M.E. report came back with just alcohol in my brother's system. No drugs or anything like that popped up on there. I just didn't believe it," Gutierrez said.
Gutierrez says he called the Medical Examiner's office.
"She had stated that sometimes...my brother's body was decomposing for so long that it was possible some of the substances may have leaked out," he said.
Dell Seton E.R. Director Dr. Christopher Ziebell says they've seen a recent wave of patients exhibiting strange symptoms after a night out on Rainey.
"We're getting some cases of people coming in who...maybe they've had one or two drinks and yet somehow they've become really profoundly intoxicated or impaired. And so the thought is that maybe something else is getting slipped into their drinks," Ziebell said.
He says they'll run tests on patients to find the cause.
"Some of the more common date rape drugs though are not detectable on our routine drug screens. So sometimes we do drug screens and everything turns out to be negative but we still have suspicion that something may have happened," he said.
The most recent incident on Rainey: Austin Police confirm they're investigating what happened the weekend of Feb. 17. A woman had a severe reaction following a night out.
"I think there are steps that people can take to keep themselves safe. We are aware of the one incident that we have right now and there's an investigation ongoing," said APD Chief Brian Manley on Wednesday at a press conference about safety and security at the upcoming SXSW.
FOX 7 asked Chief Manley what visitors to Austin should keep in mind when out on the town.
"Don't take drinks from strangers because you don't know whether or not there might have been something placed in that and if you're at a large venue and you're not with a group that may be watching your table, then don't leave drinks unattended," Manley said.
Chris Porter with the Texas Alcoholic Beverage Commission says they are investigating the incident on Rainey as well.
"So what we'll be doing is discovering, looking for evidence to see if the bar knew about anything that was happening and if so did they take any steps to prevent any illicit treatment of the customers," Porter said.
Porter says the issue is typically not with the bars, it's an individual acting alone.
"Some people are getting drugged and it needs to be acknowledged and taken care of and hopefully the police officers will take us seriously, you know especially on Rainey Street. Something is happening," Gutierrez said.