Police were alerted about a potential firearms incident in the Deighton area of Huddersfield at around 1.15am this morning.
A spokesman said evidence found at the scene in Riddings Road was consistent with a firearm having been discharged but nobody had been injured.
Six people have been arrested and are currently being questioned in connection with the incident.
A crime scene remained in place this afternoon while forensic examination of the scene continued.
Anyone with information is asked to call Kirklees CID on 101, quoting reference 13170158885.