A teenager who sparked a major emergency response after spraying shoppers with a homemade irritant inside a Costco store has been sentenced at Bristol Crown Court. Romeo Dumbi, now 18, from North Somerset, admitted four counts of administering a noxious substance following the incident at Costco, St Brendan’s Way, Avonmouth, on 17 February 2025. He was sentenced on Thursday 16 July.
Multi-agency emergency response
Police, firefighters and ambulance crews were called to the warehouse store after Dumbi sprayed members of the public with a homemade irritant. The then 17-year-old was detained by members of the public and Costco staff before officers arrived. Ten people, including Dumbi, were assessed by ambulance crews at the scene before being discharged. The incident caused widespread panic among shoppers, with many reporting stinging eyes and irritated skin. The store was temporarily closed while emergency services dealt with the incident.
Homemade spray and violent online searches
During their investigation, detectives discovered Dumbi had filmed himself making the spray using a food-grade irritant legally purchased online. Officers also uncovered internet searches showing what police described as an unhealthy fascination with serious violence.
Suspended prison sentence
Judge His Honour William Hart sentenced Dumbi to:
- 16 months’ imprisonment, suspended for two years.
- An electronic tag to monitor his movements.
- A 28-day rehabilitation requirement.
He was also made subject to a five-year Serious Crime Prevention Order (SCPO). The order places strict controls on his internet use, online accounts and internet-enabled devices, and allows police to inspect his electronic devices and access his home. If Dumbi breaches the order, he could be sent to prison to serve the suspended sentence. Breaching an SCPO is also a criminal offence carrying a maximum sentence of five years’ imprisonment.
Police praise public who intervened
Detective Sergeant Mike Coleman, of CID, praised the actions of members of the public and Costco staff who restrained Dumbi. He said:
“I would like to thank the members of the public and Costco staff who bravely restrained Dumbi until officers arrived at the scene.
“His reckless actions caused significant panic and distress to members of the public. People were complaining of stinging or itchy eyes and skin and not knowing the content of the spray in the early stages added to their concern.
“As well as the effect on individuals, Dumbi’s actions took up a large number of emergency services resources and led to the temporary closure of the store.
“Our enquiries found he has an unhealthy fascination with serious violence. The five-year SCPO will help officers to reduce the risk he poses. If he breaches the order, the 16-month custodial sentence could be enforced, and a breach is an offence in itself, with a maximum penalty of five years in prison.”
The case concluded at Bristol Crown Court on 24 July 2026.
