Pennsylvania police have said they are expanding their search perimeter after multiple recent sightings of an escaped prisoner, now on the run for 12 days.

Danelo Cavalcante stole a van and visited the homes of two acquaintances over the weekend, both outside the initial search area, a spokesman said.

Photos captured on a doorbell camera at one home appear to show the 34-year-old clean-shaven and in different clothes.

The Brazilian national's disappearance has sparked headlines in his country.

At a news conference on Monday, Deputy US Marshal Robert Clark said the manhunt had entered a new phase after the suspect was able to escape the initial search perimeter.

"In the beginning, we were prepping for the short game," said Mr Clark.

"Now we're planning in for the long game. The search in the woods was to Cavalcante's advantage."

Cavalcante was sentenced last month to life without parole for killing his ex-girlfriend Deborah Brandao, stabbing her 38 times in front of her two young children in April 2021.

He fled Chester County Prison, about 25 miles (40km) west of Philadelphia, on 31 August by "crab walking" between two walls, scaling a fence and crossing through razor wire.

The local community remains on edge, with some schools closed last week, as Cavalcante repeatedly evades capture despite being spotted several times.

Hundreds of police officers, tracker dogs and aircraft had focused their search in and around Longwood Gardens, a nearly 200-acre botanical park popular with tourists.

But Cavalcante is alleged to have stolen a 2020 Ford Transit van about three-quarters of a mile outside the search perimeter on Saturday evening. Baily's Dairy of Pocopson Meadow Farm confirmed their delivery van was stolen.

At a news conference on Sunday, Pennsylvania State Police Lieutenant Colonel George Bivens said the murderer had used the vehicle to travel to the home of a former work colleague in East Pikeland Township.

The ex-associate was not home but spoke to Cavalcante through their Ring doorbell camera.

Two photos from the camera, shared by Upper Providence Township police, capture the fugitive's now clean-shaven face. He had a beard and moustache when he escaped.

The footage also shows him wearing a baseball cap, hooded sweatshirt, green trousers similar to those in a prison uniform, and white sneakers.

The convict later tried to contact another old acquaintance, in the nearby Phoenixville area, according to Mr Bivens.

That person too was not home, and police were alerted to Cavalcante's possible sighting by a female resident.

Law enforcement believes he remains in the area and has likely entered other residences, businesses or vehicles.

"He is absolutely looking for support," said Mr Bivens. "He needs that support - he doesn't have it."

On Monday, Mr Bivens said that federal immigration agents had arrested Cavalcante's sister after she refused to assist in the investigation. Agents have initiated deportation proceedings against her, he added.

"She has failed to co-operate so there was no value in law enforcement keeping her here at this point," he said.

On Sunday, police found the van stolen by Cavalcante in East Nantmeal Township, west of his previous known locations.

It had been abandoned in a field behind a barn after apparently running out of gas, and the keys had been left inside, according to Mr Bivens.

The manhunt has now shifted to the proximity of the van's discovery, he said.

"No perimeter is 100% secure, ever," Mr Bivens told reporters. "I'm not going to make an excuse to you. I wish it had not happened."

Police faced issues with the area because it had "tunnels, very large drainage ditches, things that could not be secured", he added.

Community members have been asked to lock their vehicles and homes, monitor surveillance footage and get familiar with the latest photos of Cavalcante.

Police have been been pre-authorised to use deadly force against Cavalcante if he does not surrender.

Timeline of Danelo Cavalcante's escape and manhunt

31 August: Cavalcante escapes from Chester County Prison after "crab walking" between two walls and pushing through razor wire
4 September: Authorities begin broadcasting an audio message in Portuguese from Cavalcante's mother, urging him to surrender. He is spotted twice in the Longwood Gardens area
5 September: Police expand the search area after Cavalcante slipped past the initial perimeter, prompting the closure of two local school districts
6 September: Officials release a video of Cavalcante escaping the prison. The search area is again shifted
9 September: Cavalcante steals a delivery van outside the search perimeter and is seen on doorbell video attempted to contact former co-workers (BBC)

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