An automatic weapon is believed to have been used to kill a man in a shooting, police have said.
Gavin Parry, 31, was killed at an industrial site on Birmingham's Western Road following a gathering on 13 April.
A second man, 22, was injured and is now among 10 people arrested in connection with Mr Parry's murder.
West Midlands Police is tracing the suspected murder weapon, which it said was capable of discharging a number of shots in a short amount of time.
The force said it was "keeping an open mind" as to whether more than one gun was discharged and it was "responding to numerous leads" to recover the firearm.
It added detectives believed there was a social gathering at the scene shortly before the violence broke out.
"We're determined to find the weapons involved," Det Insp Jim Mahon, from West Midlands Police, said.
"Automatic firearms are extremely dangerous and have tragic consequences as we've seen in this case. But they can also pose real danger when they are being stored.
"We need to get illegal weapons like this off our streets before they cause more harm."
All of the 10 men who have been arrested in connection with Mr Parry's death have since been bailed, police said.
The 22-year-old who was injured in the shooting was discharged from hospital before he was questioned.
"We know that more arrests will be necessary as our investigation develops," West Midlands Police said, as it urged more people to come forward with information.
"A man has lost his life in a shooting which took place in broad daylight in our city," Det Insp Mahon said. "This is not acceptable."