Grenfell Tower Tragedy: One Year Later, Here's What We Know About the Fatal Fire

Communities in London are mourning on the one-year anniversary of the Grenfell Tower fire in North Kensington in Britain on Thursday. The fire, which took place on June 14, 2017, engulfed the 24-story building in flames and killed 72 people.

"Today we remember those who lost their lives at Grenfell Tower and pay tribute to their family, friends and loved ones for the strength and dignity they have shown," Prime Minister Theresa May tweeted Thursday.

Today, people wore green, participated in a 72-second moment of silence and attended a mass at St Helen's Church, which is close to the building, the BBC reported. During the mass, Bishop of Kensington Graham Tomlin said it was a day to commemorate those who died a year ago in the fire, The Guardian reported.

"[This is] a day for justice, as we pledge ourselves again to the slow, patient search for truth and justice for those who lost their lives, and a day for peace," Tomlin said to the congregation.

The Grenfell Tower was an apartment building constructed in 1974. The fire had broken out on June 14, 2016, at around 1 a.m. BST in a resident's kitchen on the fourth floor "in or around" a freezer, Leverhulme Research Centre for Forensic Science at Dundee University wrote in a provisional report, the BBC previously reported.

A report to the Grenfell Public Inquiry obtained by the BBC cited fire safety engineer Barbara Lane, who said the fire spread up the columns of the building and "laterally along the cladding above and below the window lines (and) the panels between windows."

In the inquiry, Luke Bisby, a professor of fire and structures at the School of Engineering, University of Edinburgh, said there is evidence that the polyethylene material in the cladding, which covers the building, was the reason the fire spread, according to the BBC.

During a public inquiry held in May, victims of family members told their stories of the disaster. Authorities have conducted a criminal investigation that could charge the companies responsible for the maintenance of the building, NBC reported.