Shanghai subway trains collide injuring more than 270
Firemen work to evacuate injured people in the underground tunnel of Line 10 after a train collision in Shanghai September 27, 2011. REUTERS

Two subway trains collided in Shanghai on Tuesday injuring more than 270 passengers, 20 critically, prompting public anger two months after a crash between two high-speed trains and renewing concerns about China's aggressive rail building plans.

The collision occurred in central Shanghai, near the Yu Yuan gardens, a well-known tourist attraction, after a signal failure meant staff had to direct trains by telephone, though they were also running at slower speeds, state media said.

The official Xinhua news agency said most of the injuries were bruises and bone fractures, and that nobody was in a life-threatening condition. About 180 people have already been discharged from hospital, it said.

Ambulances rushed to the Yu Yuan station and emergency personnel carried injured passengers out, Reuters witnesses said.

Shen Jun, 23, who was in the first coach of the train that collided at 2:51 p.m. (0651GMT), said blood was everywhere.

Many people were hurt. Look at the blood on me, on my arm, pointing at patches of blood on his shirt.

Xinhua said the signal systems used on the line were made by Casco Signal Ltd., a joint venture between China Railway Signal and Communication Corp. and French power and transport engineering group Alstom .

Casco also provided systems on the railway line where the two high-speed trains crashed in July in which 40 people were killed, Xinhua added. Reuters was unable to reach Casco or China Railway Signal and Communication for comment.

Alstom is in contact with Shanghai metro and is working closely to supply information and technical diagnostics to determine the cause of the accident, an Alstom spokesman told Reuters.

The Shanghai subway accident quickly became the most talked about topic on the wildly popular Twitter-like Sina Weibo service, coming so soon after the July incident.

Another accident -- what a joke. So much money has been spent, all they've built is crap, wrote ggirl.

Some expressed doubt the inevitable probe into the crash would uncover much.

The relevant department has already set up an investigation team -- what is this mysterious department? wondered money bag web.

China's cosmopolitan business hub is in the midst of an ambitious subway expansion plan. Shanghai now has 11 lines running on more than 400 km of track, as well as a maglev link to its main international airport.

The line the accident occurred on opened only last year. Xinhua said the same line had two system failures in the past two months.

The alarm bells are ringing again, telling us that in economic development we cannot ignore safety and must not blindly try to follow developed Western countries. We must go one step at a time, wrote ordinary interesting person.

It seems like we are going to have to revert to ancient times when we walked on foot and communicated with people by shouting. But at least we now have high-tech Weibo, added Zhao Yingying, also on Sina Weibo.

BOASTED SAFETY RECORD

Shanghai had boasted that collisions could not happen on its subway, saying in 2005 after a similar incident in Thailand that it had high-tech safeguards in place.

Today is the darkest day in the history of the Shanghai Metro's operation, said a news report by Chinese internet company Sina, citing the subway operator's official microblog about Tuesday's accident.

No matter the ultimate cause and responsibility, (we feel) particularly guilty about the harm and losses borne by the public. We will put in our utmost ability to rescue the wounded, resume operations as soon as possible ... and cooperate with the relevant departments in the investigation.

Even if our apologies pale in comparison to the actual injuries, we are deeply sorry.

However, the statement on Weibo was later removed. It was unclear why.

The accident in July involving the bullet trains triggered public fury at the government's perceived slow response and accusations of a cover-up, expressed via microblogging sites.

It also raised question marks over technology promoted as a symbol of the nation's growing prowess.

China said it would suspend new railway project approvals and launch safety checks on existing equipment to address public concern following that crash.

The high-speed train crash in July reverberated into China's stock market.

Sources said in August a $5 billion listing plan by the operator of China's new Beijing-Shanghai bullet train, initially targeted for next year, will be further delayed following July's train crash.

China Railway Group , the country's largest railroad builder, said this month it had dropped a plan to raise about 6.2 billion yuan via a share placement due to uncertainty over regulatory approval.