Three men suffered stab wounds during an incident inside the Adam and Eve pub in Bradford Street, Digbeth.
Police were called to the scene just after 4am. Roads around the pub were sealed off throughout Sunday morning.
One person was been arrested and continues to be questioned by police.
Police lifted the cordon after 2pm.
A £5,000 reward for information is being offered on the first anniversary of the shooting of a man from Leicester at a Birmingham nightclub.
Crimestoppers is offering the reward for information leading to the arrest and conviction of the person responsible for the murder of 35-year-old Sylvester Koroma.
He was shot at close range in the stomach just before midnight at The Rainbow Nightclub in Digbeth on 10 August last year and died from his injuries a week later.
Despite extensive enquiries police still need people who were to come forward with information about the night of the shooting.
Detective Chief Inspector Sab Johal, said:
We know that there were hundreds of people at the event who would have witnessed the shooting and we need these people to speak to us.
The murder has left a family devastated and officers remain determined to bring whoever carried out the shooting to justice.
I believe the answer to the murder lies in Leicester. Sylvester was from the city and travelled to the club with several associates, also from Leicester, but so far none of them have come forward to co-operate with or assist police. It is vital these people speak to us.
The mother of a man from Leicester who died after being shot outside a nightclub in Birmingham is appealing for information to help catch his killer - a year after his death.
Sylvester Koroma, 35, was shot in the stomach outside the Rainbow Warehouse on Digbeth High Street on 10 August last year.
He died a week later in hospital.
40 firefighters and 10 fire engines were called to a severe fire on the High Street in Deritend earlier this morning.
On their twitter account the fire service said two people jumped from the upper floor to escape the fire. They were treated for minor injuries and smoke inhalation. 11 other people were also evacuated.
The fire service say the fire is now being damped down and that it involved multiple properties including a three-story Victorian building.
The road has been closed and the electricity supply isolated to buildings from Heath Mill Lane to Adderley Street.
Police investigating the death of a man outside a Birmingham nightclub last month are appealing for anyone there at the time to come forward.
Sylvester Koroma from Leicester was shot in the stomach outside the Rainbow Warehouse in Digbeth High Street late on Saturday 10 August.
Seven people have been arrested in connection with the shooting but police say they're disappointed many witnesses have not come forward with information.
This week marks one year since the opening ceremony of the London Olympic Games. Small Heath boxing gym in Digbeth is just one of the projects that's benefited from the Games through funding and increased public support.
They've recently had fighters called up to represent England.
A newly restored mosaic of American President John F Kennedy has been unveiled in Birmingham today.
The artwork was built in the 1960s with money raised by the Irish community. But, despite a battle to save it, it had to be removed in 2000 to make way for building development.
The mosaic has now been recreated by an artist in Kent and returned to take pride of place in Digbeth.
Patrick O'Neill from the Birmingham Irish Community Forum, is pleased that it has returned.