The mysterious deaths of 21 teenagers at a popular nightclub in South Africa has swirled speculation and left many unanswered questions.
The incident remains under investigation by South African authorities. Here's what we know so far.
The South African Police Service said its officers were called to the Enyobeni Tavern in Scenery Park, a suburb on the edge of East London in Eastern Cape province, on June 26 at around 4 a.m. local time. Upon arrival, they discovered 17 teenagers dead inside the club. Four more died when they were hospitalized or being transported to hospitals.
Initial reports stated the death toll was 22.
MORE: Mass funeral held for 21 teenagers who mysteriously died at South African nightclubPolice said the victims ranged in age from 13 to 17 -- all under South Africa's legal drinking age of 18.
The local government, the Buffalo City Metropolitan Municipality, offered burial assistance to the victims' families. A mass funeral was held July 6.
Police announced on July 13 that the 52-year-old owner of the Enyobeni Tavern as well as two employees, aged 33 and 34, were arrested in recent days in connection with the probe. Their names were not released.
Police said the arrests were made after the Eastern Cape Liquor Board opened a criminal case against the Enyobeni Tavern for allegedly selling alcohol to minors. Investigators subsequently issued fines of 2,000 South African rand (about $118) to the two employees and served a summons to the owner for his immediate arrest and appearance in a court of law, according to police.
MORE: 3 arrested in mysterious deaths of 21 teenagers at South African nightclub, police sayThe owner is scheduled to appear in East London Magistrate Court on Aug. 19. Each of the employees was given an option to pay the fine; but should they fail to do so, they will be required to appear in the same court on the same day, police said.
Authorities will be guided by the final results of a toxicology analysis to determine whether anyone will face criminal charges for the 21 deaths, according to South African Minister of Police Bheki Cele.
The circumstances surrounding the incident were unclear but are being investigated.
"We do not want to make any speculation at this stage as our investigations are continuing," Brig. Tembinkosi Kinana, a spokesperson for the South African Police Service, told ABC News in a statement on June 26.
The Daily Dispatch, a South African newspaper published in East London, reported that the teens were attending a party at the Enyobeni Tavern to celebrate the end of June school exams. Their bodies were reportedly found strewn across tables, chairs and the dance floor with no visible signs of injuries.
South African President Cyril Ramaphosa released a statement on June 26 expressing concern "about the reported circumstances under which such young people were gathered at a venue which, on the face of it, should be off limits to persons under the age of 18."
The causes of deaths have yet to be established.
Methanol has been identified as a possible cause of the deaths, but investigators are awaiting conclusive results from toxicology testing. It is not yet known how the teens had ingested the toxic chemical.
"Methanol has been detected in all the 21 individuals that were there; however, there is still progressive analysis of the quantitative levels of methanol and whether it could have been the final cause of death," Dr. Litha Matiwane, Eastern Cape provincial deputy director for clinical service, said at press conference in East London on July 19.
Methanol is a toxic form of alcohol that is used industrially as a solvent, pesticide or an alternative source of fuel. It is not used in the production of alcohol sold for human consumption.
Alcohol poisoning and inhalation of carbon monoxide have both been ruled out as possible causes of death, although traces of both were detected in the bodies of all 21 victims, according to Matiwane.
A stampede has also been ruled out because the bodies did not show any serious injuries, according to police.
The South African National Assembly's Portfolio Committee on Women, Youth and Persons with Disabilities has called on police to "accelerate" the investigation, as the victims' loved ones await news.
"Acceleration of the investigations and the disclosure of the real cause of the deaths of the 21 children in Enyobeni tavern will certainly translate into healing for the parents and relatives of the 21 children," the committee's chairperson, Ncube-Ndaba, said in a statement on June 20.
MORE: Tear gas or pepper spray used at South African nightclub when teenagers died, eyewitness saysPolice have repeatedly declined to comment on possible causes of deaths or the circumstances surrounding the incident, citing the ongoing probe.
"Just as we said in the beginning, investigation is a process and needs to be treated with extreme care and wisdom so that we can achieve the desired outcomes which all of us will be proud of," the South African Police Service's commissioner for Eastern Cape province, Lt. Gen. Nomthetheleli Mene, said in a statement on July 13. "This is the beginning of the great work we are doing behind the scene."
All 21 victims had been identified and the autopsies were completed by June 30, according to Siyanda Manana, a spokesperson for the Eastern Cape Department of Health.
A 22-year-old Scenery Park resident, Sibongile Mtsewu, told ABC News that he was at the Enyobeni Tavern when the deadly incident in question unfolded. He said he was ordering drinks at the crowded club when suddenly the doors were closed and some type of chemical agent was released into the air.
"There was no way out," Mtsewu told ABC News in a telephone interview on June 30. "There was no chance to breathe."
Mtsewu said he passed out after inhaling the substance, which he described as either tear gas or pepper spray. He recalled being surrounded by bodies when his brother woke him up some time later.
"The tear gas suffocated many people," he told ABC News. "That's why people died."
Meanwhile, Mene, the provincial police commissioner, released a statement on June 29 expressing concern "about circulating rumours and media reports speculating on the cause of death."
"As indicated earlier, at an appropriate time and when an official report has been made available by the experts, the family and members of the public will be informed by the relevant authority," Mene said. "We urge people to refrain from making risky assumptions which do not assist our investigations."