Twelve people were killed in the US city of Chicago when a second-floor balcony collapsed during a party in an apartment building, authorities have confirmed.
Balconies are a common sight on Chicago apartment blocks
More than 30 others were injured, several seriously.
Officials said the wooden balcony gave way after being overloaded with party-goers.
As it crashed to the ground, it pulled down the balconies beneath it, crushing and trapping people below.
Eleven people were pronounced dead at the scene and another victim died later in hospital, medical officials said.
Between 40 and 50 people were reportedly on the balcony at the time of the collapse, which happened at around midnight local time in the Wrigleyville area of the city's North Side.
One 24-year-old woman who survived the accident said she heard wood splitting just before she fell.
"I am just in shock, I was just hysterical. I am just beat up and I feel very lucky," the woman, who did not wish to be named, told PA News.
Floor 'dropped out'
The majority of people at the party are thought to have been in their early 20s.
Initial reports said they were students from a local university. However, one woman who attended the party told local television that many were former classmates at a nearby high school.
Survivors and rescue workers dug through debris to reach victims
She said she was in the apartment's kitchen when the balcony collapsed.
"All of a sudden, I saw all these heads going down," she told Chicago's CLTV television station.
"The floor just dropped out from underneath them. They all went down in unison."
'Screaming and crying'
Witnesses reported seeing survivors desperately trying to pull victims from the mass of shattered wood and bodies.
Emergency workers used chainsaws to cut through debris in their efforts to rescue victims.
"There was chaos," said Chicago Fire Commissioner James Joyce. "There were people screaming and crying."
Authorities do not know what caused the collapse, but Mr Joyce said it might have been due to overcrowding.
Neighbours said the balconies, which are a common sight at the back of Chicago apartment buildings, were only built to withstand the weight of 20 to 30 people at a time.
The accident comes only a few months after 21 people died during a stampede at a Chicago club.