Body of missing pregnant Maryland teacher found; boyfriend arrested

Montgomery County police said they have arrested the boyfriend of a missing pregnant teacher after her body was found in a shallow grave Wednesday afternoon.

Laura Wallen was reported missing by her family last week after they received a text message on Labor Day that was described by police as troubling.

After nine days of searching and investigating, Montgomery County Police Chief Thomas Manger said at around noon Wednesday, detectives and a police search and rescue team conducted a search warrant in a wooded area near Prices Distillery Road in Damascus. With the help of K-9 dogs, detectives located Wallen's body in a shallow grave at a secluded field. She was around four months pregnant at the time of her death.

Her boyfriend, Tyler Tessier, was later arrested at around 5:30 p.m. Wednesday and charged with Wallen's murder. Investigators said it will be up to the Montgomery County State's Attorney's Office to determine if Tessier will face a murder charge for their unborn child.

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Chief Manger said investigators determined Tessier was the last person seen with the 31-year-old Olney woman before she died. They were captured on surveillance video at a grocery store on Sept. 2 nearby Wallen's Olney apartment. Police believe she was killed the following day.

The victim's sister received text messages from Wallen's phone on the morning of Sept. 4. But it was discovered that the texts were sent by Tessier, the police chief said.

Wallen, who is a social studies teacher at Wilde Lake High School in Columbia, did not show up for the first day of the school year on Sept. 5. Her vehicle was found a couple of days later parked at an apartment complex in the 10600 block of Gramercy Place in Columbia, which is located a few minutes away from the high school.

"Since this investigation began, Mr. Tessier has provided information to detectives that led them to suspect his involvement in this case," Manger said. "In addition, Mr. Tessier was determined to have driven the victim's car to the Columbia area. He admitted to removing the front tag and disposing of it."

Manger also said Tessier contacted an acquaintance last Sunday night asking for a ride to Baltimore and he told the person he needed help "to clean up a mess." The acquaintance refused to assist him.

Tessier also admitted to disposing Wallen's iPhone and driver's license, police said.

Manger said the break in the case came when it was determined that Tessier made several trips to an acquaintance's property in Damascus on Prices Distillery Road, leading police to obtain a search warrant. The owner of the property was not involved with Wallen's disappearance, police said.

Last Monday, Wallen's family offered a $25,000 reward for information that would help find her. Tessier appeared and spoke at a news conference announcing the reward as Laura's parents were seen holding his hand and comforting him. Tessier even made a plea for her safe return.

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"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 at the podium. "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."

However, Manger said allowing Tessier to speak at the news conference was a calculated move made by detectives and done with the approval of the victim's family.

Manger said Wednesday night he did not know the motive for the killing.

FOX 5 has confirmed through a source close to Wallen that Tessier had been living in Damascus with another woman and was in a relationship with her for years. The source said Wallen had recently found out about the situation and that may have had something to do with her disappearance.

Before the arrest was announced, FOX 5 asked police if foul play was suspected. They would only refer to this case as suspicious. We also asked if police talked to Wallen's acquaintances about her disappearance.

"That is all part of a thorough and complete investigation," said Montgomery County Police Capt. Paul Starks. "We start with the person who is missing and who that person has had contact with - family, close friends, co-workers, neighbors - and investigators begin looking at those types of people, sometimes like in this case, in an ever-expanding circle if you will."

Howard County Public Schools said in a statement Wednesday night:

It is with a heavy heart that we share the news that Wilde Lake High School teacher Ms. Laura Wallen was found deceased tonight by Montgomery County Police. We have very few additional details at this time. MCPD will hold a press conference at 8 p.m.

The Howard County mobile crisis team will be at Wilde Lake High School this evening to provide support to the entire Wilde Lake community. There additionally will be large teams of people available at Wilde Lake High School and Murray Hill Middle School tomorrow to support every student and staff member that need somebody to talk to.

The "Gathering of Hope" event scheduled for this evening has been canceled. Please keep Ms. Wallen's family in your thoughts.

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

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