Two more men have been arrested in a double murder investigation following a robbery at a cannabis factory.
Khuzaimah Douglas, 19, and Waseem Ramzan, 36, died after about seven men targeted an address in, Brierley Hill, West Midlands, on 20 February.
Police said two men aged 46 and 42 were arrested on Sunday at a property in Stoke-on-Trent.
The 46-year-old was arrested on suspicion of conspiracy to murder and is in police custody.
The 42-year-old, arrested on suspicion of assisting an offender, has been released on police bail.
It takes the total number of arrested men to five.
Micah Evans, 19, was arrested on Thursday and is due to appear before Wolverhampton Magistrates' Court later, charged with conspiracy to rob, conspiracy to burgle and perverting the course of justice.
Two men, aged 23 and 21 who were arrested on Saturday in Holyhead Port, north Wales, on conspiracy to rob have been released on police bail while inquiries continue.
Det Ch Insp Jim Munro, of West Midlands Police's homicide unit, described the latest arrests as a "significant development in our investigation" but appealed for anyone with information to get in touch.
"Every piece of information, no matter how small, could be crucial," he said.
The force is also appealing for anyone with dashcam footage of the area to contact them and say officers are continuing to reassure the community.
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