A 22-year-old man has been arrested on suspicion of murder after a fatal stabbing at a petrol station.
Pavandeep Daudher, 19, was found with a fatal stab wound to his leg at the BP garage on Lockhurst Lane in Foleshill, Coventry, at 23:00 BST on Tuesday.
The suspect was arrested from an address in Willenhall on Thursday night.
Three others - a woman, 46, and two 18-year-olds - were also held on suspicion of assisting an offender.
West Midlands Police said the arrests were a "significant step forwards" in the investigation into Mr Daudher's murder.
He died in hospital shortly after he was discovered at the petrol station with a stab wound to his leg.
His family is being supported by specially trained officers, police said.
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