Moscowvites, observed an official day of mourning Tuesday as anxious commuters returned to the metro. The death toll from the twin suicide bombings on the Russian capital's underground rose by one to total 39.

People pray for the bomb victims at the Lubyanka Metro Station in Moscow, capital of Russia, March 30, 2010. Tuesday was set as a Day of Mourning for those victims of the tragic bomb attacks. [Lu Jinbo/Xinhua]

Flags across Moscow flew at half-mast.

People laid flowers and lit candles at the stations hit by the blasts.

Many were still grieving, and some comforted others.

One day after the suicide attacks, it was not easy for these commuters to travel by metro.

Moscow Resident, said, "It's terrifying. It will be frightening for the near future but then we'll have no choice but to get on with it and trust in God."

People are criticizing a lack of security on the metro system and blaming a lack of alertness.

People mourn the bomb victims at the Lubyanka Metro Station in Moscow, capital of Russia, March 30, 2010. Tuesday was set as a Day of Mourning for those victims of the tragic bomb attacks. [Xinhua]

Commuter, said, "We saw today - they said there would be more police, but there wasn't anything of the sort. Here anyone could get into the metro quite easily - if the police were more alert of course, I don't think it would have happened."

Russian leaders have vowed to hunt down the masterminds of the twin suicide bombings which were carried out by two women.

Vladimir Putin, Russian Prime Minister, said, "We know that they are keeping a low profile now. But this is a matter of honor for the law enforcement agencies to drag them out from the depths of the sewer into the daylight. I am sure this will be done."

No claims of responsibility have been made.

Many have speculated that the blasts - blamed on extremists in the Caucasus region, which includes Chechnya - were in retaliation for the recent killing of separatist leaders in the area by Russian police.