Passengers on Muni's N-Judah line reportedly experienced a harrowing ride Wednesday morning when the train seemed to accelerate out of control and was unable to stop.

The incident happened around 8:38 am Wednesday, as KQED was first to report. The crowded N train was traveling inbound between Cole Valley and Duboce Park when passengers say the train seemed to speed up unusually. As the train emerged from East Portal, it reportedly blew past the Duboce and Noe stop and through the S-curve onto Duboce Avenue at dangerous speed.

Luckily, there were no cars on the street as the train barrelled into the shared roadway, and the driver seemed to regain control of the train at the bottom of the hill at Sanchez Street, bringing the train to a full stop.

"It was like 'This might be it!'" says one friend of SFist who was on the train, adding that people onboard were crying.

"It was definitely scary," says Jack Logar, relaying the story to KQED. "I had people fall on me as we were going around the first curve. There were a couple loud yells, but then the train didn’t really stop immediately."

Logar added that "for at least five seconds, maybe longer, the train was just flying."

Witnesses allegedly said that they heard the train operator, who appeared rattled, mutter something about how the train wouldn't stop.

After stopping near Duboce Park Cafe, all the shaken passengers reportedly exited the train there. The train then pulled forward to the Church and Duboce stop, and then may have been taken out of service.

The SFMTA has yet to issue any official public statement about the incident, but a spokesperson did respond to one Redditor who posted about it on Wednesday.

"We understand that this incident may have been concerning and do apologize for any distress it may have caused you," the agency said. "Our preliminary review indicates that the vehicle is mechanically sound and operating properly. We are continuing to investigate the circumstances of the incident and will take any appropriate corrective actions to ensure the continued safety and reliability of our system. We appreciate you taking the time to share your observations and concerns with us."

Another passenger on the train, who commented on the Reddit thread, indicated that driver error could have been to blame. "[The train] didn’t start braking where it’s supposed to towards the last quarter of the duboce tunnel and went into the bend at full speed and tossed everyone into each other. Really thought it was going to derail when we came out of the tunnel at full speed," the passenger wrote.

This is a developing story and may be updated.