OTTAWA -- Ottawa's LRT system was out of service in the east end for 30 minutes Friday afternoon after someone was spotted on the tracks.

OC Transpo said on Twitter at 3:08 p.m. that the O-Train was out of service between St. Laurent and Blair stations due to a "disturbance on the tracks."

R1 replacement bus service was deployed between St. Laurent and Blair stations Friday afternoon while the train was out of service.

At 3:53 p.m., OC Transpo reported regular service had resumed in the east end.

"Special Constables have helped unauthorized person off the tracks safely," said OC Transpo on Twitter.

"Regular service between St-Laurent and Blair stations has resumed and all platforms are now open."

City staff told CTV News Ottawa LRT service was shutdown in the east end for about 30 minutes.

OC Transpo special constables continue to investigate the incident, including determining why the unauthorized person was on the tracks.