Police in Northern Ireland have opened an investigation after a teenage girl died at a local music festival, and a man died soon after it ended.

According to the BBC, the Irish News and Belfast Media, 17-year-old Mia Keevan of County Tipperary, Ireland, became ill at the Emerge music festival in Belfast and died soon after in a local hospital. Trae Keenan, 24, from County Down, Northern Ireland, died in a rental property just a few hours after the event ended.

Two other people also became ill while attending Emerge, which took place from Aug. 24 to 25, and are still hospitalized, the outlets reported.

“During the event, it was reported that a 17-year-old girl had become unwell. Sadly, she subsequently died in hospital,” police superintendent Allister Hagan said in a statement.

A police spokesperson also confirmed to the Belfast Telegraph that a man in his 20s — later identified by media as Keenan — “was taken to hospital, and later died.”

“Enquiries are ongoing and a post-mortem examination will take place in due course,” the spokesperson added.

Hagan added in his statement that a number of arrests were made during the two-day event, but did not specify if they were related to the two deaths.

“Officers made seven arrests over the weekend and issued 13 immediate disposals — three Fixed Penalty Notices, one Caution and nine Community Resolution Notices,” he said. “Offenses included disorderly behavior, driving whilst unfit through excess alcohol, assault on police and possession of controlled drugs.”

Police urged the public not to speculate on the cause of the deaths until the local coroner releases their findings.

“First and foremost, we need to remember that at the center of this debate there are two grieving families,” Hagan added to Belfast Media. “They remain in our thoughts.”

Keenan’s family told the Irish Times that they do not believe his death was related to drugs.

According to the BBC, Emerge is the largest dance music event in Northern Ireland, attracting around 40,000 people each day. This year’s lineup included headliners Fatboy Slim and Bicep, as well as techno, EDM and other musicians such as Sammy Virji, Fjaak, Sonny Fodera and Danny Howard.

Shine Productions, which organized the music festival, did not immediately respond to PEOPLE’s request for comment.

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In a GoFundMe organized on behalf of Keevan’s family, a friend remembered the teenager as a “bright, fun and much-loved girl who touched the hearts of anyone that knew her.”

“Mia was such an outgoing person and lit up everyone room she walked into,” the post reads. “Her laughter and warmth will never be forgotten by those lucky enough to have known her.”

At a funeral service held in her Irish hometown of Carrick-on-Suir — located about 200 miles outside Belfast — mourners said that Keevan was “the happiest she had ever been” ahead of her 18th birthday.

“She had this way of making everyone laugh, no matter how annoyed you were at her, you couldn’t stay mad for long because she would already be on to her next plan, scheming about what she was going to do next,” her sister Kyah said, per ITV.

“She ran her own race, always on her terms and we loved that about her,” Kyah continued. “She had big dreams — visiting me in Australia was one — and there was always new ones popping into her head every single minute.”

“Mia did not just walk quietly through life, she ran, she danced, she climbed,” Father Paul Waldron said at the service, per ITV

“She was always chasing after something that mattered, she lived her adventures,” Waldron added. “She was clever, she was cheeky, she was mischievous in the best of ways, she had a spark in her eye when she told you she knew exactly what she was doing, usually it was something fun or something a bit bold, or maybe both.”

Keenan, the father of an infant son, was remembered as an “adventurous young man” who had a passion for sports and had recently worked as a chef, per Belfast Live.

“He loved his adventures with his friends, which also led to them being very boisterous together. He also loved being an uncle… being best in the company of his family and friends,” a mourner said at his funeral service on Friday, Aug. 29.

“Life became good when he met his partner, Tiffany, and he became a loving father to baby Mason,” they added.

Superintendent Hagan told Belfast Media that police are encouraging festivalgoers to take various safety measures, including around drug use.

“Alongside our investigation, we will continue to take practical steps at events and festivals to reduce harm,” he told the outlet. “From drug amnesty bins to rapid testing of the seized or surrendered drugs and sharing intelligence through [Drug and Alcohol Monitoring and Information System], we are working closely with health partners and event organizers to help keep people safe.”

Festivalgoers are asked to “look out for each other and seek help immediately if someone appears unwell.”

“If you or a friend need help, contact event medical staff or approach a police officer or steward,” police said, per Belfast Media.