Neighbours have told of their horror after a woman was hurled more than 40 feet from a block of flats.
The 32-year-old sustained serious chest and leg injuries during the terrifying incident early yesterday morning.
She has been named locally as Aisling Smyth.
A 26-year-old man — understood to be well-known to her — is being questioned on suspicion of attempted murder.
The incident occurred at around 4.50am at the Spring Meadow flats complex off the Springfield Road in Belfast.
People described seeing a woman lying on the ground outside the building, surrounded by clothes.
The scene was sealed off throughout the day as detectives attempted to piece together the circumstances.
Neighbours said there had been an argument at a nearby pub earlier in the evening.
A stretch of road at Colligan Street was also taped off by police for part of the morning.
One man who lives near the scene said he was shaken by the news.
“It is horrific — I just hope the girl pulls through,” he said.
“The drop down is 40ft or more from the window; it’s a miracle she survived at all.”
Another described how a scuffle broke out as police arrested a man in connection with the alleged murder bid.
He was also detained on suspicion of assault on police and resisting officers.
Horrific evidence of the incident was still visible yesterday morning.
The windows of the top floor flat where the woman fell from were still open, while clothes, including a pair of pink shoes, lay strewn on the ground.
A length of cable could also be seen hanging out of the window. Part of it had snapped and was lying on the pavement.
A woman who lives in the complex, who declined to be named, said she was awoken by screams around the time of the incident.
“I heard shouting and soon afterwards there were police sirens. There seemed to be a real commotion going on,” she said.
Sinn Fein councillor Jim McVeigh said the community’s prayers were with the victim.
“This is a tragic incident which has left a young woman seriously injured,” he said.
“Our prayers are with this woman and her family at this very traumatic time.”
The PSNI has appealed for witnesses to contact it on 0845 600 8000. Information can also be passed anonymously to Crimestoppers on 0800 555 111.