The way police responded to phone calls made before a shooting outside a Liverpool pub is being investigated.
Two doormen were shot in the legs outside the West Derby Hotel at about 2215 BST on 15 August.
The Independent Police Complaints Commission (IPCC) said four calls were made to police from the pub - the final one an hour before gunmen opened fire.
The doormen, aged 21 and 22, were treated in hospital but are said to be making a full recovery.
No-one has been charged over the incident.
Two men, aged 21 and 27 and from Stockbridge Village, were arrested but released on bail.
A statement from the IPCC said: "The IPCC investigation is looking at the police response to four telephone calls received from the public house over a number of days, particularly one call received approximately one hour before the shooting relating to a possible threat."