Houston Police Department and Harris County Sheriff's Office rushed to NRG Park to secure the scene, but said they found no evidence of a shooting.
EYEWITNESS VIDEO: Hundreds run for cover at RodeoHouston
The all-clear was issued around 10:40 p.m., but people on social media still say they believe a shooting occurred.
"We have no weapons or suspect in custody and nobody has been shot," HPD Captain Dwayne Ready said.
He also answered the question about the possible source of the alleged noise.
RAW VIDEO: Police update on the investigation at RodeoHouston
"It could be that somebody heard something loud as they passed something," Ready answered.
As the shelter-in-place was in effect during the night, eyewitness described the chaos that unfolded.
"All of a sudden we seen some juveniles running," an eyewitness told ABC13.
ABC13 Digital Managing Editor Brittany Guarglia was inside Wednesday night's concert when the announcer broke the news over the intercom.
"There has been a situation on the ground, everyone must stay indoors right now," the announcer initially said.
"All you heard was gunshots," another eyewitness told us, describing how people were shoving each other and pushing to get out of what they thought was a dangerous situation.
"Mobs of people running, I did see some people trampled," a bystander said.
The carnival remained open after the investigation, RodeoHouston officials confirmed.
Investigators were said to be speaking to a person of interest. No injuries were reported.
The Houston Livestock Show and Rodeo issued this statement overnight:
The safety of our Houston Livestock Show and Rodeo guests is always our highest priority.
Show security is staffed by officers from the Houston Police Department, Harris County Sheriff's Office, and the Texas Department of Public Safety. HPD has investigated the incident reported at NRG Park Wednesday night and has stated that they have found no weapons, have no suspect is in custody, and there are no reported injuries. As a precaution, Show officials instructed people to shelter in place for a short time until officers determined that conditions were safe.
We will continue working closely with HPD, HCSO and Texas DPS to monitor the situation.
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