At least 24 people are still hospitalized--12 in critical condition--after the Grenfell Tower in London burst into flames Wednesday. @Natalie Oxford / Twitter

By James Masters and Faith Karimi

LONDON (CNN) -- As London mourned the victims of a building inferno that left 30 people dead, Queen Elizabeth reflected on the somber national mood Saturday, a day after she visited the site.

The Grenfell Tower erupted into flames Wednesday in a deadly blaze that left 24 people still hospitalized -- 12 of them in critical condition.

Queen Elizabeth and Prince William, the Duke of Cambridge, visited the area and met residents and community representatives Friday.

In her official birthday message a day later, the queen addressed the latest tragedy to hit the nation.

"Today is traditionally a day of celebration," Queen Elizabeth said in a statement. "This year, however, it is difficult to escape a very somber national mood. In recent months, the country has witnessed a succession of terrible tragedies."

She said her visits to London and Manchester --- the latter the site of a terror attack last month -- have highlighted the people who offer comfort and support those affected.

"Put to the test, the United Kingdom has been resolute in the face of adversity," she wrote. " United in our sadness, we are equally determined, without fear or favor, to support all those rebuilding lives so horribly affected by injury and loss."

Protests

Residents furious over the handling of the Grenfell Tower disaster descended on the local town hall in west London Friday, shouting, "We want justice."

Some wore T-shirts with images of missing loved ones as they climbed the front steps and pushed their way into the building.

A second protest began later at Britain's Home Office, which oversees fire prevention and policing nationally. Organizers handed out fliers that read, "Your anger must be heard." The protesters eventually made their way to busy Oxford Circus, where they staged a sit-in.

Theresa May, Britain's embattled Prime Minister, is facing criticism for failing to meet residents when she visited the scene Thursday.

The UK has promised a full public inquiry, and announced a fund of 5 million British pounds ($6.4 million) to help those affected by the blaze.

London Mayor Sadiq Khan demanded that the government publish a list of other tower blocks checked by investigators. In a letter to May, he listed a litany of residents' concerns, including a lack of information about missing relatives, the chaotic response of the local council and worries over safety in other tower blocks.

"They feel the government and local council haven't done enough to help them in the aftermath of this horrific incident, or to provide answers to their increasingly urgent questions," Khan wrote.

Police have opened a criminal investigation into the circumstances of the blaze. They examined the apartment where the fire started and determined "there is nothing to suggest the fire was started deliberately." A team of senior detectives is investigating.

One London member of Parliament has called for corporate manslaughter charges after learning flammable material was used to clad the building during the recent renovation. No sprinkler system was installed.

Victims' details emerge

The names of those who died are beginning to emerge.

One was Gloria Trevisan, 26, an Italian architect living in London because her family was having financial difficulties at home in Italy.

A lawyer for the family told CNN that Trevisan spoke with her parents before she died, telling them: "I am going to heaven. I will help you from up there."

Mohammad Al-Hajali, 23, a refugee who fled Syria for the UK in 2014, was identified as another victim.

Mohammad and his brother Omar, both students, lived together on the 14th floor.

Omar, 25, survived, but the brothers were separated as firefighters tried to rescue them from the burning building early Wednesday.

Blame game

The UK government has promised that all those left homeless by the disaster will be rehoused in the local area. But the government has been criticized for failing to act on recommendations from previous tower block fires.

The Prime Minister is facing particular scrutiny over the role of her new chief of staff, Gavin Barwell, who served as housing minister until he lost his seat in last week's snap general election.

Barwell had told lawmakers that the government intended to review fire safety standards following a fatal fire at Lakanal House, a London high-rise in 2009. Three women and three children died. Exterior paneling helped the fire spread.

CNN's Angela Dewan, Eliza Mackintosh and Jeanne Bonner contributed to this report.

The-CNN-Wire

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