A double murder inquiry has been launched in the Moss Side area of Manchester after two people were stabbed, police said.
Greater Manchester Police (GMP) said two people had died “despite the best efforts” of emergency services who had been called to Great Southern Street at about 05:00 GMT.
A man has been arrested on suspicion of murder, the force said.
A cordon has been established and GMP has asked people to avoid the area.
No further details have been released about those who died.
Police have not yet disclosed any more information about the man they have taken into custody.
Reporting from the scene, BBC News journalist Molly Brewer said she could see a green bike lying on the ground.
Local residents had opened their front doors to ask police for information about what had happened, she said.
“It’s very, very scary,” said one woman, who did not want to be named.
“I worry about my kids because the place is not safe.”
Another said: “I’ve never seen anything like this before round here – it’s a complete shock”
As of 10:00, there were about 10 officers standing on the edge of the cordon.
An earlier post on GMP’s Facebook account for Longsight & Moss Side read: “There is an emergency services presence on Great Southern Street in Moss Side whilst officers respond to an incident.
“Police have attended and despite the best efforts of emergency services, two people were treated at the scene and have sadly been pronounced dead.
“We have arrested one man on suspicion of murder.
“Please avoid the area as there is a large emergency service presence while we establish the full circumstances of the incident this morning.”