Students at Cambridge University say they're "appalled and shocked" to discover that police have been attempting to infiltrate and spy on their activities.
An undercover video has emerged of a student being asked by an officer to feed information on politically active campaigns and protest groups.
Cambridgeshire Police says its tactics are within the law, but civil liberty groups say it's an infringement of fundamental rights and covert operations on innocent groups should be banned.
Click below to watch a report from ITV News Anglia's Tanya Mercer
More top news
Dry with clear or sunny spells. Winds easing overnight.
Very warm with sunshine. Chance of thundery showers late morning.
A hot, humid and sunny start before cloud increases as a narrow band of thunderstorms spreads northeast. These clear during the afternoon.