An 18-year-old man has been arrested on suspicion of murder after three people died in a tower block.
Bedfordshire Police responded to concerns about the welfare of some residents and discovered three injured people in a flat in the Marsh Farm area of Luton at about 05:30 BST.
All three people were pronounced dead at the 15-storey Leabank building and following searches police found a weapon.
Det Supt Rob Hall said: “As part of our investigation, we have recovered a firearm from Bramingham Road and inquiries will be ongoing in relation this.”
Armed police and investigators wearing white forensic gear were spotted at the tower block and a nearby open green space.
The 18-year-old was arrested that morning on neighbouring Bramingham Road.
Det Supt Hall added: “We are still in the early stages of this investigation and formal identification of the victims has yet to take place. However we do believe that all of those involved are known to each other and we are not currently looking for anyone else in connection to this incident.
“We’ll have officers working around the clock both at the scene and in the community over the weekend and I would encourage anyone with concerns to speak to their local community officers.”
He added there was not believed to be any threat to the wider community.