Streetcars are back running on Queen Street today, nearly 72 hours after they were pulled from the route over concerns about damage that mysteriously appeared in more than two dozen of the vehicles.

The TTC made the decision to replace streetcars with buses on its 501 and 508 routes at around noon on Wednesday after it found similar damage affecting the emergency braking system on 25 different low-floor streetcars.

In recent days, the TTC has painstakingly inspected the entire route using a special streetcar outfitted with cameras in its wheel well to search for any debris or issues with the track that could have caused the damage.

While the initial source of the damage remains unclear, the TTC has been able to do determine that there are no current safety concerns along the route.

As a result, the TTC announced at around 6 a.m. on Saturday that full streetcar service had resumed along Queen Street.

“After two full test days, with consultants helping, Queen deemed safe for TTC streetcars,” spokesperson Stuart Green said in a message posted to Twitter. “Track work in a few spots early in the week likely resolved the cause and nothing new found. Crews making good progress on damaged cars.”

The TTC previously said that streetcar service was not likely to resume until Monday morning.

There were about 80 buses serving the route during the service interruption.