Laura Wallen's murder linked to love triangle, police believe

Authorities believe a Howard County teacher was murdered after her boyfriend found out she was going to talk to his fiance about being pregnant with his child.

Laura Wallen's body was discovered in a shallow grave in a field along Prices Distillery Road in Damascus, Maryland on Wednesday. Prosecutors said in court on Thursday that Laura Wallen's clothing was seen protruding from the ground. Shortly after the discovery, her boyfriend, Tyler Tessier, was taken into custody and charged with murder.

Just days earlier, Tessier stood with Laura Wallen's family and fought back tears at a news conference.

"Laura, if you are listening, it doesn't matter what's happened, it doesn't matter what type of trouble, there is nothing we can't fix together - myself and your family," Tessier said to reporters at Monday's news conference. "There are so many people, so many people that miss you, so many people who were out, who haven't slept. We haven't eaten. We are just looking or praying that you are safe."

But police said having Tessier address the media was part of their strategy, hoping that he would catch himself in a lie about the death of the Wilde Lake High School teacher who was four months pregnant with his child.

On Thursday, Laura Wallen's father Mark Wallen addressed the media for the first time after learning the news of his daughter's death. He said as the investigation moved forward, police asked him and his wife to appear at the press conference and to act as if they were supporting Tessier, even though they knew authorities were suspicious of him. Mark Wallen said standing with Tessier at the news conference was the hardest thing his family has done.

"He is a monster and he is a liar and it was absolutely the hardest thing that my wife could do, would be to sit there next to him and hold his hand and she had to hold his hand with two hands because she was shaking so badly," Mark Wallen described. "We were pretty sure it was Tyler but we didn't know where she was and you can't put somebody away on a missing person. Someone doesn't go to prison for life on a missing person and it defies description the awfulness and the horror that we have been put through during this."

MORE: Father of Laura Wallen gives heartfelt statement about his daughter's murder

Authorities revealed that they believed the motive behind the killing was connected to a love triangle. Tessier was engaged to be married to another woman, and authorities said Laura Wallen had recently reached out to her to set up a face-to-face meeting. Investigators believe she was possibly going to tell the woman she was four months pregnant with Tessier's child

Laura Wallen was first reported missing on Sept. 4 by her sister. Police determined that the last known financial transaction from Laura Wallen's account was a debit card purchase at a Safeway in Olney, Maryland on Sept. 2 between 8:30 p.m. and 9:30 p.m. The store's surveillance cameras showed Laura Wallen and Tessier making a purchase together.

Police said the last message from Laura Wallen's phone was to her sister on the morning Sept. 4. It was a text message detectives said Tessier admitted to sending himself.

Officers said an employee of the Gramercy Place apartment complex in Columbia, Maryland located Laura Wallen's license in front of an apartment dumpster on Sept. 4. When police responded they also found Laura Wallen's vehicle, a 2011 black Ford Escape.

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Between Sept. 5 and 11, detectives said they interviewed Tessier multiple times. They said in each interview, Tessier provided conflicting statements regarding Laura Wallen's disappearance. Police said Tessier also admitted that he drove Laura Wallen's vehicle to the apartment complex in Columbia, Maryland and disposed of her phone and driver's license in a dumpster, and then removed her license plate from her vehicle.

Police said they located an acquaintance of Tessier who told them that Tessier had called her and asked her to give him a ride from the apartment complex where Laura Wallen's vehicle was located. Investigators also said Tessier asked the friend to lie if police ever asked her about picking him up. Detectives said Tessier contacted an acquaintance last Sunday night asking for a ride to Baltimore for help "to clean up a mess." The acquaintance refused to assist him.

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Authorities said Tessier had been spending a lot of time at the property where Laura Wallen's body was eventually found after her reported disappearance. During the search, police said they located a freshly dug area of the ground in a field adjacent to the friend's property. It was there they said they discovered Laura Wallen's body.

At his bond review hearing on Thursday a judge told Tessier he was "a danger to the community" and was denied bond. Prosecutors told FOX 5 they didn't believe anyone else was involved in Laura Wallen's murder. Her body was taken to the Medical Examiner's Office in Baltimore for an autopsy to determine an exact cause of death. The results of the autopsy have not been released yet.

FOX 5's coverage on the disappearance of Laura Wallen:

Body of missing pregnant Maryland teacher found; boyfriend arrested

Missing pregnant teacher's family offers $25,000 reward

Vehicle of missing pregnant Maryland teacher found in Howard County

Students coming together to help in search for missing pregnant Md. high school teacher

Wilde Lake High School students hoping for safe return of missing teacher Laura Wallen

Search continues for missing pregnant Maryland teacher

Police searching for missing pregnant Maryland teacher