A signaling glitch caused a massive, rear-end train crash on the Metro Line 10 in central Shanghai near Yuyuan Garden early yesterday afternoon, sending hundreds of injured passengers to hospitals.

At least 20 were seriously injured but the injuries were not life-threatening.

A total of 271 people have received treatment in hospitals, Xu Jianguang, director of Shanghai's health bureau, said at a press briefing late yesterday.

By 7 p.m. yesterday, 91 were still hospitalized. The others were discharged.

"This is the darkest day ever for the Shanghai subway. Regardless of the cause or responsibility, we are stricken with remorse for having caused our passengers injury and losses," the Metro operator said in an apology posted on its blog. "We want to deeply, deeply apologize."

The victims generally suffered bone fractures, bruises and cuts after they were thrown against the hand rails and windows, doctors said. The most seriously hurt patients suffered brain and spinal injuries and fractured skulls, said the doctors.

At least seven hospitals were involved in emergency rescues.

The victims included four foreigners - two Japanese, a Canadian and a Filipino. They all made it through with minor injuries, government officials said.

The crash occurred about 2:50pm when a low-speed train crashed into another that had been on standstill ahead of it for nearly 40 minutes, according to witness accounts and Metro officials' reports.

The crash took place about 700 meters from Line 10's Laoximen Station near the Bund. Both trains had left from the previous stop at Yuyuan Garden Station, a well-known tourist attraction, .

Because of a signaling problem, traffic on a stretch including the two stations had been slowed down, with limited speeds and operated manually instead of by the normal automatic system.

The Metro authority so far has not explained why the first train had stopped for so long during the slowdown period. Passengers onboard that train told Shanghai Daily that they were only told by the driver to be patient before the collision.

At 6:30 p.m. at the Laoximen Station, injured victims were still being helped out on stretchers to be taken to hospitals.

"The train had been running slowly for a long time but the collision was heavy," recalled an elderly patient in a lot of pain yesterday afternoon at the Ruijin Hospital. The patient, who was on the second (moving) train, was waiting in a wheelchair for further checks and might have broken ribs.

"You have to be brave, son. We were lucky to survive," the still-frightened man said with tearing eyes and short breaths while on the phone to his son.

Hospitals opened special sections to offer emergency aid to the victims.

Doctors suspected they would find more victims with brain concussions and other internal injuries after more observation.

A local TV news report showed the property damage - interior structures of the collided carriages on both trains distorted and inclined to one side, and some windows completely smashed.

The less seriously injured helped each other walk through hundreds of meters along the track to reach the surface at both the Laoximen and Yuyuan Garden stations. Dozens of ambulances, fire engines and police cars were dispatched to support the rescue operation. The sound of sirens lingered in the air for hours.

Nearby roads were put under restricted traffic and hundreds of transit buses were added to boost rush-hour capacity on affected routes.

Traffic on Line 10 resumed with limited speed at 7:10 p.m. During the rescue period, 13 stations on the line had been closed.

However, today the line will be closed between the Yili Road and Sichuan Road North stations for rechecks of the safety system, based on a recommendation by investigators. Officials didn't know how long the closure would last.

(Shanghai Daily September 28, 2011)