Hundreds of tower block residents have been told to leave after "major structural faults" were discovered.
Bristol City Council has declared a major incident after building surveys showed Barton House in Redfield would not be safe in the event of a fire or explosion.
In a press briefing the council said residents had been told to leave and stay with friends and family, or go to designated rest centres.
About 400 people live in the building.
The BBC is running a live page on this developing story.
Residents are being told to pack enough clothes and belongings for "a day or two" the council said.
Staff are knocking on doors, sending texts and "getting in contact with everyone in the block" telling them to leave "as soon as possible", it added.
The council said it had been carrying out building surveys on Barton House, the oldest in its estate, as it decided on the long-term future of the block.
During the surveys, experts discovered that the building's structure could be "compromised" in the event of a fire, explosion or large impact.
Further surveys are planned but in the meantime, the authority said it was going door-to-door telling residents to leave.
Declaring a major incident allows the council, which has said the issue is not related to RAAC concrete, to seek help from outside organisations.
This afternoon's Bristol City Council meeting was postponed after the news broke.
Local GP surgery Wellspring Settlement said on X (formerly Twitter) said it was likely to be an information point.
The emergency services have been put on standby as a precaution, Bristol City Council said.
'Children are panicking'
Nuh Sharif, who has lived in Barton House since 2012, said he was "panicking".
A tearful Mr Sharif, who has two children, said his partner had been told the building "might collapse".
"We need to go somewhere quiet because they [his children] panic and can't sleep.
"I am worried where they are going to stay. How am I going to get them to school tomorrow?"
Yousif Ahmed, who lives in Barton House with his wife and children, aged two, four and six, said the council "should have warned people earlier".
"They have just suddenly come knocking on the door saying you have to leave."
Mr Ahmed was packing some belongings in his car when he spoke to the BBC, and said he does not know where he will go.
An Avon Fire and Rescue Service spokesperson said it has been liaising with the council since they undertook their survey on the tower block.
"As a precautionary measure and to allow for further, more in-depth surveys, residents in the block are being asked to leave immediately," they said.
"The approach the Council are taking as responsible owners of the building is appropriate and proportional, we are in support of this to ensure that residents are kept safe."
Another resident told the BBC he found out about the evacuation from Facebook and a friend.
He said Barton House "should have been condemned year ago".
"My flat is terrible. It's full of damp and mould.
"Half my ceiling has collapsed literally into my bathroom."