Four boys have been arrested in connection with the murder of a 52-year-old man in north London, according to media reports quoting police sources.
The boys, believed to be aged 13 and 14, are suspected of stabbing a man to death following an argument with the victim, according to Xinhua.
The man was pronounced dead shortly after police and ambulance personnel arrived at the scene.
Police said there was a "supervised party" taking place at another address within the block and the group of boys was trying to gain access to the place.
"The victim and this group were not known to each other, what started as a minor verbal altercation has escalated into a shocking act of violence," said Neale Baldock, detective chief inspector of the Metropolitan Police.