Three police specials were 'spat at and bitten' during an attack in Bolton.
The three police volunteers were assaulted on Friday night in the town.
Mike Walmsley, chief officer of Bolton GMP Specials, described the attack as 'absolutely unacceptable'.
CO Walmsley did not disclose where the assaults had taken place.
Writing on Twitter, he said: "Last night three of our Bolton @GMPSpecials were assaulted.
"They were bitten, spat at and hit by 3 'people' who were then arrested. Disgusting behaviour and absolutely unacceptable."
Fellow GMP colleagues shared their disgust at the attackers' behaviour.
Chief Inspector Jamie Collins, of Bury district, replied: "3 officers giving up their own time to protect and serve the public of Bolton.
"This sort of incident is all to common now in policing but will not be tolerated. 3 suspects arrests and later charged with assault. "
He added: "Bitten, spat at in the eyes and punched.
"Absolutely disgusting and hard to believe this is the world we live in.
"Totally unacceptable. These officers are not even getting paid for giving up their precious family time to serve their community."
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