The suspect, aged in his 30s, was detained after a Range Rover was stopped in Hunter Street in Carnforth at around 11.30am yesterday (Thursday, October 1).
It follows a Lancashire-wide manhunt for the suspect, who is accused of shooting two men dead at an industrial estate in the West Midlands on Wednesday (September 30).
It’s understood the victims – aged in their late 20s/early 30s and yet to be formally identified – were killed at an industrial estate in Dudley shortly after 1pm. Their bodies were found inside a vehicle parked outside units at 3.30pm.
The murder suspect is then alleged to have fled the West Midlands and driven up the M6 to Lancashire.
A manhunt followed and police later arrested the man after swooping on a black Range Rover outside the Co-Op in Carnforth.
Officers searched the vehicle, but did not find a firearm.
The man was arrested on suspicion of murder and taken into custody, where he remains this morning.
Detective Chief Inspector Jim Munro, Homicide Unit, said: "This is a fast moving investigation, a real team effort involving officers who’ve worked around the clock since the discovery of the bodies to trace the person we believe is responsible.
"The arrest is a significant development but our enquiries continue and I would appeal to anyone with information about what’s happened, or anyone who was in the area at the time and saw or heard anything suspicious, to get in touch."
Following the man's arrest, officers visited Poulton Industrial Estate off Garstang Road, where they told businesses they would need to close the yard to search for a murder weapon.
Staff at Ashvin Metal said they were told that the murder suspect is believed to have visited the site in an attempt to dispose of the gun.
A search is taking place at the site this morning.
Anyone with information is asked to contact West Midlands Police on 101 quoting log 3204 from September 30.