Two men were found with knives concealed in their pants after police carried out a routine traffic stop for lane hogging on a motorway.

Thames Valley Police officers spotted the Mercedes C250 on the outside lane on the M4 between Newbury and Reading in the early hours of Monday on a mostly empty carriageway.

When stopped the driver provided a positive roadside drug test for cannabis.

Using a peach emoji in a social media post - commonly used to symbolise a bottom - police said a "subsequent search in custody revealed a knife concealed somewhere that really doesn't need further explanation", while the passenger had a 2ft (61cm) zombie knife tucked into his waistband.

Several thousand pounds in cash was also discovered on the two men.

"At this point, our straightforward lane discipline stop had developed more plot twists than a Netflix crime drama," a police spokesperson said.

The Mercedes was driving at about 90mph when first seen by the roads policing team.

After the police vehicle flashed its headlights several times, the driver moved into lane two before returning to lane three, prompting officers to stop the vehicle.

As well as a positive drug wipe for cannabis, herbal cannabis and cannabis resin were also found. The driver only had a provisional UK licence.

Both occupants were arrested on suspicion of being concerned in the supply of a Class B drug.

The 18-year-old passenger entered a guilty plea at Slough Magistrates' Court on Tuesday in relation to the possession of an offensive weapon and was granted bail.

The driver remains bailed pending further enquiries and blood analysis.

The police spokesperson said: "We started with someone who couldn't quite grasp the concept of 'keep left' unless overtaking... all because lane one apparently wasn't good enough."

They added: "You really never know what you're going to find when you stop a vehicle."