Police rushed to St Peter’s Square just before 8.30pm.
No one is thought to have been injured in the incident.
Officers were responding to reports of a suspected firearms discharge and a car crash.
Three people have been arrested over the suspected firearms discharge.
Two 16-year-olds and a 19-year-old were arrested on suspicion of dangerous driving and possession of a firearm.
When emergency services arrived at the scene, they found an abandoned vehicle on the Metrolink tram tracks in St Peter’s Square.
The two boys and man remain in custody.
Superintendent Helen Critchley, from GMP’s City of Manchester division, said: “We understand that this incident has no doubt caused concerns in the city centre and those living nearby but I’d like to reassure them that a thorough investigation is underway.
“Officers are at the scene and a large cordon is in place whilst a number of enquiries are carried out to establish what happened during this incident.
“Three arrests have been made and our efforts to piece together what happened continue.
“Anyone who was nearby at the time or has any information is asked to get in touch.
“Any details may prove vital and those with information can call 0161 856 4409 quoting log number 2989 of 27/02/2021.
“Alternatively, contact Crimestoppers anonymously on 0800 555 111.”
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