Fresh searches in the disappearance of Madeleine McCann have entered a second day as police clear undergrowth near the banks of a remote reservoir in Portugal.

Officers were working with strimmers and heavy machinery at the Barragem do Arade on Wednesday, around 30 miles from where Madeleine went missing in 2007.

A fire service vehicle and rigid-hull inflatable boat were also on the banks of the reservoir.

Other officers with a sniffer dog were seen entering an area of woodland as the search continued, while colleagues carried spades and rakes.

The fresh searches are being carried out at the request of German investigators who believe their prime suspect, convicted sex offender Christian Brueckner, 45, kidnapped and murdered the little girl.

He is currently in prison in Germany for the rape of a woman in Praia da Luz in 2005, and is suspected of further rapes and child sexual abuse committed in the area between 2000 and 2017.

German authorities have not revealed what triggered the latest search operation, but prosecutor for the city of Braunschweig Christian Wolters said they were acting on the basis of “certain tips”.

He told German public broadcaster NDR: “We have indications that we could find evidence there. I don’t want to say what that is exactly, and I also don’t want to say where these indications come from.

“The only thing that I would clarify is that it doesn’t come from the suspect — so we don’t have a confession or anything similar now, or an indication from the suspect of where it would make sense to search.”

The Sun reported that investigators previously found photos and video of Brueckner at the reservoir. He has reportedly denied any involvement in Madeleine’s disappearance.

Madeleine vanished while on holiday with her parents in Praia da Luz, after they left her and her younger twin siblings asleep in their apartment while they went out to dinner with friends.

Portuguese lawyer Marcos Aragao Correia previously claimed that criminal contacts had told him that Madeleine’s body was in the reservoir, and in 2008 he raised funds for unsuccessful private searches of the water.

Four teams of officers from the Portuguese Policia Judiciaria are involved in the operation, along with at least 20 of their German counterparts, Portuguese news outlet SIC said.

British officers from the Metropolitan Police are also present while the work is carried out so they can inform Madeleine’s parents if there are any developments.

On Tuesday, search teams were seen scouring the banks – hammering away at the ground with pickaxes and combing through small rocks with rakes and spades.

Around a dozen officers with sniffer dogs were also at the site, while the fire service boat took officers onto the water.

Portuguese daily Expresso said that the first day ended with no significant results, and that police had collected some objects including fabrics and garments.

Madeleine’s disappearance has attracted enormous media attention since she vanished, and reporters are being kept at arm’s length around a mile away from where search activity is taking place.

A no-fly zone has also been imposed over the reservoir.

The new searches come as the Home Office granted an extra £110,000 in funding this financial year for the Metropolitan Police to assist with finding Madeleine, down from just over £300,000 last year.

The total funding given to Operation Grange has been just under £13.1 million since 2011.