Authorities in Pennsylvania who have been trying to capture an escaped murderer for nearly two weeks pushed back Monday against questions about whether they blew a chance to collar him, instead blaming the complex terrain in the initial search area for the fugitive’s success in getting clear of it.

Top state and federal officials insisted that the blown perimeter around the area where hundreds had been searching for Danelo Souza Cavalcante includes heavy woods, underground tunnels and drainage ditches. They also said it took more than two hours for news to reach them that he had been spotted outside of the perimeter for the first time.

At a news conference, they rejected the suggestion that they haven’t been using enough searchers and insisted that the effort - in its 12th day Monday - favors them, despite the fact that there is no longer a well-defined perimeter or any fresh sightings to report.

Robert Clark, the supervisor of the U.S. Marshals fugitive task force in Philadelphia, contended that law enforcement teams have the advantage now that Cavalcante is apparently in a less rural environment in suburban Philadelphia.

“Now we’re going to prepare for the long game, and the long game is what we do best,” Clark said.

Philadelphia State Police posted early Tuesday on X, formerly known as Twitter, that the department was pursuing Cavalcante in Chester County. “He is armed. Residents in the area are asked to lock all doors and windows, secure vehicles, and remain indoors,” the post said. Police also asked that the public call 911 if Cavalcante is seen and not to approach him.

Cavalcante slipped out of the 8-square-mile search area over the weekend, stole a dairy delivery van that had been left unlocked with the keys in it, and drove it until it practically ran out of gas.

He abandoned it in a field behind a barn more than 20 miles north of the search area, after unsuccessfully seeking help at the homes of two former colleagues late Saturday, police said.

Lt. Col. George Bivens, of the Pennsylvania State Police, declined to say how he thinks Cavalcante slipped through the perimeter, but he said no perimeter is completely secure.

Cavalcante is desperate because he is reaching out for help from people with whom he hasn’t spoken in years, he said.

“The fact that he has reached out to people with a very distant past connection tells me he doesn’t have a great network of support,” Bivens said. “So I think he’s desperate and I’ve characterized him as that all along. And I think the longer we push him, the more resources, the more tools we bring to bear, we will ultimately capture him. He doesn’t have what he needs to last long-term.”

Cavalcante, 34, has eluded capture since Aug. 31, when he broke out of the Chester County Prison while awaiting transfer to a different lockup. He had been sentenced to life in prison for fatally stabbing an ex-girlfriend in 2021, allegedly to stop her from telling police that he’s wanted in a slaying in his home country of Brazil.

To escape, Cavalcante scaled a wall by crab-walking up from the recreation yard, climbed over razor wire, ran across a roof and jumped to the ground. His escape went undetected for more than an hour until guards took a headcount. The tower guard on duty was fired, officials said.