Friends and family looking for Pat Lamb have endured another agonising afternoon of fruitless searching.

Girlfriend Natasha Morgan was told this morning that two different lorry drivers had seen the missing 28-year-old near Allington Lock.

She quickly drove to the area, where she was joined by a small team of volunteers helping in the search.

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Lock keeper Tim Benger showed them through the morning's CCTV to see if there were any sightings but Mr Lamb did not turn up on the cameras.

They then met with Kent Search and Rescue's Steve McGowan, who was speaking with a police Marine squad carrying out a routine check.

Video: New 'sightings' leader to search for Pat Lamb

Mr McGowan said: "I saw an update on the Help Find Pat Lamb Facebook page so I came along. I live nearby.

"There's been a constant presence from either us or the police but we haven't found any sign of him.

"There's a lot of debris in the river, including sunken boats and a caravan. That's how hard the task is, it's a big river and that's assuming he's even in there."

Volunteer Helen Stockman added: "We are not just looking for Pat, we are looking for a mobile phone or any other clue.

"We are also looking to get hold of any CCTV footage that hasn't yet been seen. There's lots of companies that are just coming back from Christmas and we hope they can help with that."

The broadcast engineer, from Greenhithe, has been missing since he went on a night out to Maidstone with friends nearly a month ago.

Yesterday search teams visited traveller yesterday in an attempt to find new leads.

On Sunday gypsy sites around Maidstone were visited but no new leads were gained.

Today his family will visit Canterbury after a member of the public called to inform search teams of a potential sighting.

The woman believes she may have seen him near the Fenwick Store, in St George's Street, a little over a week ago.

His family will visit the city centre to see if anyone else has information to back up the information.

Mr Lamb, who lives in Greenhithe, has been missing for close to a month.

On Saturday his friends and family also searched the woodland area at the Farthing Corner service station on the M2 coastbound, near Gillingham, and the Medway Towns.

"A woman who thinks she may have seen him in Canterbury and let us know just in case. That was a week ago but we will see if we can find anything..." - Zoe Lamb, Pat Lamb's sister

Sister Zoe Lamb said: "It was just another weekend of searching. We had someone contact us about a possible sighting on the M2 but we didn't see anything.

"We also looked around Strood, Chatham and Rochester.

"I spoke to his girlfriend Tash yesterday and she told me about a woman who thinks she may have seen him in Canterbury and let us know just in case. That was a week ago but we will see if we can find anything."

The broadcast engineer disappeared after a night out in Maidstone.

Several CCTV images show him walking through the town centre and his whereabouts are now the focus of a major operation involving police, Kent Search and Rescue, family, friends and even strangers.

Specialist police and teams using search dogs have also been brought in.

The timeline so far:

Friday, December 12, 11.42pm: Mr Lamb seen on CCTV in Gabriel’s Hill. Door staff pointed him in the direction of some paramedics at the top of Gabriel’s Hill, but he did not speak to them.

11.47pm: Seen in Jubilee Square at the top of Gabriel’s Hill and the High Street, having purchased a sandwich at Subway in Gabriel’s Hill.

11.59pm walks down the High Street to the junction with Pudding Lane. A CCTV image of this has been published.

Saturday, December 13 00.07am Mr Lamb seen on private CCTV in Pudding Lane, making his way into a small car park behind the shops, where he remains for approximately 11 minutes.

00.20am Having used a small alleyway to come back out onto Earl Street, Mr Lamb crosses Fairmeadow and takes a flight of steps to the river side. This has been corroborated by a reliable witness statement. A CCTV image of this has been published. This is the last sighting of him.

01.34am: His phone goes ‘offline’ from the mobile phone network. It is not known if Patrick was in possession of his phone when it went offline.