Houston firefighters stationed outside of the Astroworld concert venue Friday night were not in radio communications with the emergency medical providers hired by the concert organizers as the deadly crowd swell unfolded, the city’s fire chief told CNN on Tuesday. According to the president of the city’s firefighter union, the Houston Fire Department officials on standby had asked the concert organizers for a radio to communicate with ParaDocs, the emergency medical providers, but were only provided with cellphone numbers. CNN has reached out to ParaDocs for comment. A total of 528 Houston police officers were inside the venue as well as 755 private security personnel and members of the ParaDocs medical team, CNN has reported. Patrick M. “Marty” Lancton, president of the Houston Professional Fire Fighters Association, said that cellphones are not a reliable communication method during emergencies, given potential signal weakness during events involving large gatherings. “Seconds matter, minutes matter in emergencies,” Lancton told CNN. One man told Houston City Council on Tuesday that cell service did not work during the event, and that service was so bad he couldn’t text his friends who were standing just feet away from him. The fire department had set up outside the venue as a proactive measure and was in radio communication with the Houston Police Department, according to fire Chief Samuel Peña. “We were in direct communications with the Houston Police Department, and we were in communications with the Harris County Emergency Corps, which was providing some of the transport units for that event,” Peña told CNN’s Victor Blackwell. Pressed on whether the fire department was in communication with the concert organizers during the event, Peña said they were not. “No, on scene we did not have direct communications with those organizers,” Peña said. As the mass casualty event unfolded, the fire department rushed its resources into the crowd, eventually transporting 12 “very critical” victims, in many cases with CPR in progress. Three people remain hospitalized Tuesday in the chaos that left eight people dead and dozens more injured. Among those severely hurt Friday was a 9-year-old boy who’s in a medically induced coma, his grandfather said. Two survivors are in critical condition, Houston Fire Chief Samuel Peña said. Concertgoers described disaster as a countdown clock ticked down to headliner Travis Scott’s performance. Once the show started, cries for help went unheard as the music roared. “They passed out. And they were on the ground and basically getting trampled. And no one would pick them up,” concertgoer Billy Nasser told CNN on Monday. “There was just too many people there. It was overcrowded. The way the barricades were set up had people trapped in. It was a death trap.” Investigators in Houston are working to determine all possible causes of death and injuries to concertgoers, including whether a batch of counterfeit pills possibly laced with fentanyl played a role, according to The Wall Street Journal, citing people familiar with the investigation. CNN is reaching out to authorities for comment regarding The Wall Street Journal’s reporting. In response to that reporting, Peña told CNN that while there was evidence drugs may have been involved, officials do not have information on what those drugs were. “All that is going to be fleshed out, I believe after the investigation,” Peña said. GET LIVE UPDATES Toxicology reports will have to be a key part in helping assess what happened, Harris County Judge Lina Hidalgo said Monday. “That’s going to take weeks,” she said. The FBI in Houston said it has offered its “assistance and resources” to local police. While organizers have had issues with crowd control in the past, it is too early to draw conclusions about exact causes of death, Hidalgo said. “There’s a lot of evidence of drug use. Could that have been part of it? It’s hard for these families to grieve without answers,” she said. It could take up to several weeks before ruling on causes of death, said Michele Arnold, a spokesperson for the Harris County Medical Examiner’s Office. Among those injured was a security officer who “was reaching out to restrain or grab a citizen and he felt a prick in his neck,” Houston Police Chief Troy Finner said. The officer went unconscious and was revived after medical staff administered Narcan, a drug used to treat narcotic overdoses. Live Nation and Drake among named defendants At least 18 lawsuits related to the festival had been filed by Monday evening in Harris County District Court in Texas. Event organizer Live Nation Entertainment was named as a defendant in all but one of the suits, while Scott was named in most. Other people and organizations involved in the concert, including NRG Stadium as well as actor and musician Drake, were named in at least one of the suits. “The injuries have had a serious effect on the Plaintiff’s health and well-being. Some of the effects are permanent and will abide with the Plaintiff for a long time into the future, if not for his entire life,” one of the lawsuits stated. Other lawsuits allege serious injuries from being “trampled” during the crowd crush as well as “emotional distress.” The lawsuit in which Drake is named accuses him of helping to incite the crowd as the “surprise guest” alongside Scott, both of whom stayed on stage as “the crowd became out of control,” the suit says. Drake posted Monday on social media: “My heart is broken for the families and friends of those who lost their lives and for anyone who is suffering. I will continue to pray for all of them, and will be of service in any way I can.” Scott tweeted on Saturday: “I’m absolutely devastated by what took place last night. My prayers go out to the families and all those impacted by what happened at Astroworld Festival.” NRG told CNN in a statement it is unable to comment at this time. CNN has reached out to Scott, Live Nation and others named in the suits. Show continued during crowd surge Scott will cover all funeral costs for those who were killed, according to a statement Monday from a representative. “Travis remains in active conversations with the city of Houston, law enforcement and local first responders to respectfully and appropriately connect with the individuals and families of those involved,” the statement reads. “These are the first of many steps Travis plans on taking as a part of his personal vow to assist those affected throughout their grieving and recovery process.” Some city officials say more responsibility lies with Scott for continuing to perform while many in the crowd were under duress. And crowd control has been an issue at his shows in the past. Mayor Sylvester Turner on Tuesday released all permits filed with the city for this year’s Astroworld Festival, which show that in the 2018 and 2019 festivals “there were a lot of transgressions on the Main Street side of the yellow lot. Those included destroying property and various acts of violence,” according to an email from NRG park to city officials. The permits and email messages provided were from the Mayor’s Office of Special Events, the Houston Health Department and the Houston Fire Department (HFD). “The list of permits is not exhaustive, as some [permits] were filed with Harris County,” Turner said in a statement. Turner said he was making the documents available to the public “in the interest of transparency and amid great public interest.” Scott pleaded guilty to disorderly conduct in Arkansas in 2018, according to the Northwest Arkansas Democrat Gazette, after police say he encouraged people to rush the stage at a 2017 show. Two other misdemeanor charges, including inciting a riot, were dismissed. Scott maintains he had no idea the extent of what was happening in the crowd during Friday’s show. Footage from the concert’s live stream also showed Scott pausing his performance and looking on in apparent confusion as an ambulance pulled into the crowd before finishing the concert. The fire chief believes if Scott had ended his performance sooner, it may have calmed the crowd, he said. “If the lights would have been turned on – (if) the promoter or the artist called for that – it would have chilled the crowd, and who knows? Who knows what the outcome would have been? But everybody in that venue, starting from the artist on down, has a responsibility for public safety, I believe,” Peña told CNN on Monday. Yet at a Saturday news conference, when asked why the show was not stopped sooner, the police chief cited potential rioting “when you have a group that’s young” in a crowd of roughly 50,000 people. There was a “discussion between promoters, the fire department, the police department, and NRG officials” about stopping the event,” Finner said.