A man who had been shot and was found dumped in a street had been doused in both acid and alkaline, police said.
Liam Smith’s body was discovered on Kilburn Drive in Shevington, Wigan, at about 19:00 GMT on 24 November.
Greater Manchester Police (GMP) said the hazardous substances found on the 38-year-old’s body were alkaline and acid, at opposite ends of the pH scale.
Detectives are investigating whether the combination was an attempt to destroy evidence or part of the attack.
The body was found on a patch of rough ground between houses which leads to a dirt track and open fields.
Image caption, Liam Smith’s body was found on Kilburn Drive in the Shevington area
The hazardous substances were not believed to pose any further harm or risk to the public and have been contained, GMP said previously.
Mr Smith was described by his family as the “most devoted dad” and “the life and soul of the party”.
Det Ch Insp Gina Brennand previously said the “shocking murder of a much-loved family man” was the first fatal shooting in the area for more than two years.
She urged anyone who had seen “anything unusual or out of the ordinary near to the victim’s home” on Thursday to contact police.
“We are determined to recover the weapon and find Liam’s killer,” she said.
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