(CNN) -- Law enforcement officers in northern England continued their search Thursday for a man who allegedly shot three people, one of them fatally, local authorities said.
Armed officers have been searching since Saturday for suspect Raoul Thomas Moat in the area around Rothbury in Northumberland but have been limited at times by poor weather conditions, according to Northumbria police.
"The searches in this area have proved a particular challenge due to the open farmland and dense woodland, and officers are continuing in their efforts today," Temporary Deputy Chief Constable Jim Campbell said.
Moat allegedly wounded his ex-girlfriend, fatally shot her new boyfriend and shot a police officer.
"I'd like to reassure the public that we are doing everything possible to locate Moat and bring this investigation to a conclusion," Campbell said.
Campbell said that although much of the inquiry centers on Rothbury, it is just one part of a complex investigation. Two men have been charged in connection with the investigation and were to appear in court Thursday, he said.
Campbell declined to name the two individuals.
The father of Samantha Stobbart, Moat's ex-girlfriend, on Wednesday urged the suspect to turn himself in.
"Raoul, son, please, this has to stop. We don't want anyone else hurt," Paul Stobbart said in a video released by police.
Detective Chief Superintendent Neil Adamson said Wednesday that Moat had been living in a tent in a secluded spot near Rothbury. Police recovered the tent and an eight-page handwritten letter, purportedly from Moat to his ex-girlfriend.
The letter contained personal messages for Stobbart, and in it Moat asserted that her boyfriend was a police officer. Police contend that was not true.
Moat has been on the run since the shootings Saturday.
The five-day, large-scale search operation for the 37-year-old man police call "armed and dangerous" has involved a number of police units across Northumbria, including specialist search teams, armed response units, helicopters and dog handlers, according to police officials.
In a public address, Adamson had what he called a personal message for the suspected killer: "Don't leave your children with the wrong memories of their father. You still have a future. Give yourself up now."
The two people injured in the shootings remain in the hospital in what authorities described as critical but stable condition.