The police have so far withheld details of what caused a massive number of emergency services to descend on a south Belfast neighbourhood.

The incident, whatever it was, led to "four people and a number of police officers" being taken to hospital, said the PSNI.

All have since been discharged.

The PSNI have not said how many officers were taken to hospital, but said that they went there "as a precaution".

placeholder image — Police alongside colleagues from other emergency services at Damascus Street in south Belfast (picture by Arthur Allison/Pacemaker Press)

News of the incident first broke at 7pm on Tuesday, when police issued a statement saying: "Police alongside colleagues from other emergency services are at the Damascus Street area of south Belfast after a number of people became unwell this evening."

Damascus Street is in the Holylands – a densely-packed district of the city, populated heavily by students.

Pictures emerged showing PSNI, fire brigade, and ambulance crews at the scene.

Later that night, the PSNI said that four people plus police had been taken to hospital due to "potential contact with a possibly noxious substance in the property" but that "there is no wider risk to the public at this time".

Then this morning police said: "An investigation has been carried out and no noxious substance was detected.

"A quantity of suspected drugs have been removed from the property and enquiries remain ongoing."

It appears that the Ambulance Service was the first emergency service to be called.

It said in a statement that it had "received a number of 999 calls shortly after 5pm on Tuesday... following reports of an incident".

The police were called at around 5.15pm, meanwhile the fire brigade were called at around 5.30pm.

The fire brigade said that "crews utilised detection and monitoring equipment to assist in resolving the incident" – though, like the other services, did not specify what the nature of the incident was.

The Ambulance Service confirmed that it sent four crews. On top of this were an unconfirmed number of fire engines from Belfast, Lisburn, and Dromore, plus an unconfirmed number of police (the BBC reported from the scene that there were at least six fire engines and three police vehicles present).

The Ambulance Service told the News Letter today that all media enquiries should be directed to the PSNI, echoing what the fire brigade had said the night before.

The police were asked how many officers went to hospital, how many emergency service personnel attended the scene, what was meant by people falling "unwell", what had made those people "unwell" if no noxious substance was found, and whether anyone was arrested in connection with the drugs found (among other questions).

It refused to go beyond what it had said earlier.

It comes after criticism of the authorities in August over a lack of information about the deaths of two young people.

Mia Keevan and Trae Keenan died after they had attended the Emerge music festival in Belfast, while at least another two attendees of the event were hospitalised.

At the time, former Lord Mayor of the city Micky Murray declared himself "incredibly disappointed" at the lack of detail from the authorities, while BBC presenter William Crawley said there were "big public interest questions" for the Public Health Authority and police, but that "the silence has been deafening".