Toronto's busiest subway station was shut down Tuesday morning amid reports of an explosion and an ensuing fire in a tunnel adjacent to the platform.

Just after 10 a.m. on Tuesday, the TTC tweeted that service had been halted between St. Clair and College for reports of a fire, deploying shuttle buses between St. Clair and Bloor stations.

Line 1 Yonge-University: No service between St Clair and College while we respond to a report of a fire.
Shuttle buses have been ordered and will operate between St Clair and Bloor stations.

— TTC Service Alerts (@TTCnotices) April 25, 2023

CityNews shared exclusive video captured from the station's Line 1 platform, showing what reportedly began as an electrical fire raging just beyond the station platform.

All the while, commuters can be seen lining the platform edge, phones in hand, for a chance to record the chaos.

CityNews captured video of a fire on TTC Line 1 tracks at Bloor/Young station around 10am.
According to CTV, it was small and extinguished by Toronto fire.
Line 1 service is not running between St Clair and College (4 stops unserviced). Line 2 service is bypassing Bloor/Young pic.twitter.com/HB41gu5nxw

— Simon Hopkins (@Reporter_Simon) April 25, 2023

Emergency crews responded to the scene, and the fire has reportedly since been extinguished, however, there has been no update from the TTC on the resumption of train service on the busiest stretch of the Line 1 subway.

UPDATE: 

The TTC tweeted at 3:18 p.m. that crews had isolated a faulty cable at the scene of the fire, and had deployed 60 shuttle buses to offset the temporary disruption.

Chaos on @TTCnotices Yonge University Line. No subway service between College and St Clair. In line for shuttle buses. Not the better way. pic.twitter.com/A4h3ln8x5r

— Glenn Sumi (@glennsumi) April 25, 2023

Around 4:30 p.m., the TTC added that "Crews have got service back up and running on Line 1 Bloor/Yonge and on Line 2," and that "35 shuttle buses will continue to operate to supplement service."