Cat-calling culprits might think twice before yelling out, honking or making gestures at women out for a run, as they might be undercover cops.

They look like your average evening joggers — pounding the pavement in running gear, headphones on, dodging the post-work rush.

But in Surrey this month, some of those female runners have been carrying more than water bottles. They’ve been packing badges.

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As part of a new “Jog On” campaign, undercover police officers are hitting the streets in a bid to expose the harassment faced by women simply trying to go for a run.

Two female officers took to known “harassment hotspots” in Reigate during rush hour, wearing plain athletic gear but backed by specialist units lurking nearby, ready to intervene.

It didn’t take long. Within ten minutes, a man in a large truck honked and made gestures out of the window. Thirty seconds later, another vehicle slowed down, beeping and leering.

“That’s how frequent it is,” Inspector John Vale told reporters from LBC, who joined the operation.

“Someone slowing down, staring, shouting, even if it’s not always criminal, it can have a huge impact on people’s everyday lives. It stops women from doing something as simple as going for a run.”

Police admit much of the behaviour they encounter — honks, shouts, lingering stares — doesn’t always meet the threshold for criminal charges. But the campaign is designed to draw a line in the sand before harassment escalates into something more sinister.

The force says it has already made 18 arrests in the past four weeks for offences ranging from sexual assault to theft, with many more “educational interventions” for less severe incidents.

PC Abby Hayward, one of the undercover runners, said the harassment is so common, it’s almost background noise.

“It’s something many women experience every day,” she said. “It needs to be addressed.”

A Surrey County Council survey of 450 women earlier this year found 49 per cent never reported incidents like catcalling, a stat police say underscores the need for proactive patrols.

Critics of the program include the Free Speech Union, which said the tactic was a “bizarre social-psychology experiment,” and that police should enforce the laws on the books, according to the outlet.

With some commenting, “So it’s not actually a crime, but you’ve assigned a large amount of resources to try and stop it? Why not assign those officers to dealing with domestic abuse or doesn’t that look as good on Insta?”

But Inspector Vale is unapologetic.

“We have female officers and staff who’ve been targeted when they’re off duty,” he said.

“The message is clear: your actions will not be tolerated. The next time you see a female jogger, just think she could be a police officer with colleagues nearby, ready to stop you.”

Surrey Police plans to keep the trainers on and the campaign running a warning to anyone who thinks catcalling is just a harmless pastime.