Transcript for Mexican authorities investigating after US student plunges to his death

Next tonight, to a parents' horror. It's that time of year. Spring break is now here, and tonight, we've already learned of a college student plunging from the seventh floor balcony of his hotel in cancun. What his girlfriend and what witnesses are now reporting tonight, and here's ABC's erielle reshef. Reporter: Tonight, Mexican authorities investigating after a Michigan college student plunged to his death from a seventh floor balcony at this cancun hotel. A tragic end to what was supposed to be a spring break getaway. The girlfriend of 19-year-old Ahmed altaii reportedly telling police he had been drinking and consuming toxic substances before his fatal fall. Krystal Herndon and her husband, who were staying on the same floor, say altaii looked upset earlier that night. We opened our hotel door to see what the noise was and saw him, you know, angrily pacing toward the hallway and her trying to grab him to get him to sit down. Reporter: His former classmates back in Michigan now grieving. I really I didn't even believe it. It just hurts. I'm still in shock that he's gone. Reporter: Mexican authorities say this is a private investigation and are not providing any details. We did reach out to that hotel, David, they are not commenting. Tough time of year when we start to hear those headlines. Erielle, thank you.

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