Allan Schoenborn might have tried to kill himself after his children were slain in Merritt, B.C., in 2008, a court was told Friday. (CBC)

Evidence found in the trailer home where three B.C. children were slain suggested that their father may have tried to kill himself before leaving the trailer where their bodies were eventually found by their mother, a B.C. judge heard Friday.

RCMP forensic investigator Const. Jennifer Clark testified at the murder trial of Allan Schoenborn that crime-scene photos show a bloody extension cord leading to a bathtub and a bent razor blade in the blood-spattered bathroom.

The defence and Crown submitted a list of agreed facts to B.C. Supreme Court Justice Robert Powers, which included that most of the blood evidence found in the home was from Schoenborn.

Crown prosecutor Sheri Mark told the judge that Schoenborn's blood was found on clothing, splattered in the hallway, smeared in the bathroom and covering a long-bladed kitchen knife in the master bedroom.

Powers, who is hearing the case without a jury, has already heard that five-year-old Cordon and eight-year-old Max were suffocated, while their sister, 10-year-old Kaitlynne, was stabbed to death. The judge was told that much of the blood found in Kaitlynne's bedroom was her own.

Schoenborn, their father, is being tried on three counts of first-degree murder.

Under questioning from defence lawyer Peter Wilson, Clark said Schoenborn had injuries to both his forearms and hands when he was found later wandering in the woods.

Left wallet and clothing behind

"There was evidence that some kind of clean-up had been conducted?" Wilson asked after reviewing pictures of the bathroom in the home.

"It did appear, the water was diluted [with blood] and there was soap with blood on it," Clark replied.

Forensic investigators seal off the mobile home in Merritt, B.C., where three children were killed in 2008. (CBC)

Pictures of the scene also indicate that Schoenborn left behind warm clothing and his wallet, which contained a credit card, his identification and pictures of this three children.

Schoenborn was a fugitive for more than a week before he was spotted, hungry and dehydrated in the woods.

The first man to come across him told the court on the second day of the trial it was the Schoenborn family dog that convinced him the man was the suspect police were looking for.

Pat McCoy lived on the same street as the children, whose bodies were found on April 6, 2008. He testified that he first recognized the family's dog and then saw a man curled up under a coat in the woods just a few hours' walk from the home.

"I saw a green coat with feet sticking out of it."

Gash on forearm

McCoy was running back to alert police when he met up with local hunter Kim Robinson, who took out his rifle and approached Schoenborn.

He had been missing for 10 days since the children's mother found the bodies in her trailer.

Under cross-examination by Wilson, McCoy said he saw injuries on Schoenborn's arms when he came across him in the woods.

"He had a good gash on his left forearm," McCoy replied.

The deaths rocked the small ranching community of Merritt, located about 270 kilometres northeast of Vancouver.

Before the deaths, Schoenborn had several run-ins with the law.

Police arrested him three times in the week before the killings, including for allegedly uttering threats at his children's elementary school, and there was a restraining order restricting him from contact with his wife.

The trial, which is taking place in a Kamloops, B.C., courtroom, is scheduled to last about a month.