By Sarah Rainsford BBC correspondent in Moscow

As the first of the walking-wounded emerged into daylight from Paveletskaya station, many struggled to absorb the enormity of what had happened.

The public is blaming Chechen separatists for the attack

Moscow has been hit by suicide-bombers before. But the target this time has shocked everyone.

The train exploded on a packed commuter line at the height of rush hour. Dozens of people were killed in their seats.

Irina works outside Paveletskaya station and she watched as the dead and injured were evacuated in front of her. Sobbing quietly, she could barely believe the scale of horror she had witnessed.

"I used to trust in God for protection," she said. "Now I'm terrified. I can't believe that you can just go out to work one day, and never return."

It's like we're at war on our own doorstep Alexei Metro passenger

The Moscow Metro system is one of the busiest in the world carrying close to nine million passengers every day. For many in the city it is a transport lifeline.

Now, it has proven a soft target for terror.

By Friday evening, a full Metro service had been restored and life in the capital was returning to normal. Left with little alternative, crowds of resigned Russians were heading back underground.

Public anger

Russians are famously fatalistic. But many passengers admitted to feeling nervous.

"It's like living on a battlefield," Alexei said as he made for the escalators. "It's like we're at war on our own doorstep."

The underground system was soon running as normal

"The Metro is my only way of getting around," another passenger added. "But now I'm terrified something will explode."

Underground, investigators worked their way through the twisted wreckage of the train in a hunt for clues. With the rescue operation at an end, the next task is to identify whoever was behind this attack.

But up at street level, many people have already drawn their own conclusions. Taking their cue from the Russian president, they are pointing the finger of blame towards separatist fighters from Chechnya.

Spokesmen for the rebels deny any involvement - but support for the Kremlin's tough tactics in the war-torn southern republic is increasing regardless. Hearts here, are clearly hardening.

"We should never have listened to those liberals," one man said. "We have to crush the terrorists. To be very, very tough with them. It's the only way."

"This just shows we need to crack-down on all people from the Caucasus" another man told me. "We need to do more document checks, to see exactly who they are."

Security has been stepped-up now across the capital. Outside metro stations, police officers have been warning passengers, through megaphones, to be on their guard for any form of suspicious activity.

But there is a clear sense here that it is far too little - and too late. Initial public shock at the blast quickly turned to anger and a conviction that the attack should never have happened.

There is scepticism too, at talk of increased security measures on the Metro.

"What good will it do?" one woman said. "They can't possibly stop and search everyone. The only thing we can rely on, is our luck."