A southbound Q train derailed in Brooklyn this morning, according to the MTA. No injuries were reported.

The train derailed north of the Brighton Beach B/Q station. MTA spokesman Kevin Ortiz said that according to a preliminary investigation, the second set of wheels on the second car of a southbound Q train came off the rails shortly before 9 a.m. A so-called reach train "is currently on scene removing customers from the incident train," Ortiz said.

B trains are currently suspended between Broadway-Lafayette and Brighton Beach in both directions; they are running between 145th Street and 2nd Avenue. Some southbound Q trains are running on the N line from Atlantic Avenue-Barclays Center to Coney Island, and some are terminating at Kings Highway.

The MTA is encouraging riders to take the C and D as an alternative in the Bronx and Manhattan, and the B16, B41 or B68 buses in Brooklyn.

This is a developing story—we will update soon. Check Twitter and MTA.info for updates on service changes.

Last month, an A train derailed in East Harlem, injuring more than 30 people.

With Jake Offenhartz.

[Update 10:15 a.m.]: There were 135 passengers on the southbound Q train when it derailed, according to a transit source, though the FDNY reported a higher number, 300. A reach train backed up to the derailed Q train, and passengers walked through the reach train to exit on the platform at Sheepshead Bay.

[Update 11:25 a.m.]: An FDNY spokesperson confirmed at a press conference that no one was seriously injured aboard the derailed train. He said that one pregnant woman was complaining of back pain and is being evaluated at Lutheran Hospital as a precaution. The derailment was a "minor incident," the spokesperson said, as there were no customers stuck in tunnels and the power was only briefly turned off inside the train. An inspection safety unit is currently examining the derailed train, which is expected to take a minimum of four to five hours.

[Update 12:00 p.m.]: "The Summer of Hell is turning into the Summer of Fear,” said Nick Sifuentes, deputy director of the Riders Alliance. "Our ongoing crisis is exactly what happens when the State skimps on decades of transit investment. Riders are scared and angry—and they’re not going to let up on the governor until we have the funding we need to fix our subways."

[Update 3:15 p.m.]: A transit source told DNAInfo that today's derailment marked the second derailment in the area in recent weeks. According to the source, a maintenance train derailed at the nearby West 8th Street stop on July 9th. MTA spokesman Kevin Ortiz did not confirm the derailment, but told the news website that a "high-rail vehicle" had a "mechanical issue" at that station on July 9th. The NY Post also reported that a "work train" derailed twice in the area on July 9th, while working near West 8th Street, citing an anonymous union source.

“This same train derailed at Coney Island Yard yesterday,” the source said. “The MTA knows this train has an issue and they sent it out to the main line anyway.”