BALTIMORE (WJZ)-– A missing Maryland teacher who was four months pregnant has been found dead and her boyfriend has been arrested and charged with her murder, Montgomery County police say.

We are sad to report that missing Olney woman Laura Wallen has been located deceased. A suspect was arrested for her murder 45 minutes ago. — Montgomery Co Police (@mcpnews) September 13, 2017

Laura Wallen was found dead Wednesday in a shallow grave in Damascus off Prices Distillery Road.

Wallen’s family and friends became alarmed last week when she didn’t show up for the first day of classes at Wilde Lake High School in Columbia.

“We had a real sense of dread this is the way this was going to end up,” said Montgomery County police chief Tom Manger.

Boyfriend Tessier, now wanted for Wallen's murder, held hands with her parents at press conference! @cbsbaltimore #LauraWallen pic.twitter.com/45uRZHp6yJ — Mike Hellgren (@HellgrenWJZ) September 14, 2017

Police say Tyler Tessier, Wallen’s longtime boyfriend, had been a person of interest even as he held hands with Wallen’s mother on Monday and pleaded for her safe return at a press conference.

“There is nothing we can’t fix together, myself and your family,” Tessier said at the conference.

Police say Wallen’s parents knew he was a suspect as detectives noticed inconsistencies in his story.

“The decision to allow him to participate in that news conference was a calculated decision made by the detectives in this case with the expressed purpose of hearing what he had to say,” Chief Manger said.

Investigators believe Tessier may have killed Wallen on September 3, and then drove her SUV to an apartment complex near the Mall in Columbia and ditched it there.

They also say he admitted to removing the front tag of her SUV, and to throwing away her license and phone.

Police recovered surveillance video of the two at a nearby supermarket the day before she went missing.

Police say Wallen, who lived in Olney, last contacted family members by text message on Sunday. But investigators believe Tessier was the one who sent a message from Wallen’s phone to her sister’s phone saying the baby wasn’t his.

Tessier dated Laura Wallen for 10 years; addressed her Monday in front of tv cameras, asking her to come home; she was dead @cbsbaltimore pic.twitter.com/KDzunbXjZR — Mike Hellgren (@HellgrenWJZ) September 14, 2017

“This is one of those tragic cases where you have an absolutely innocent victim,” Manger said. “Just senseless, senseless killing.”

Police said Tessier texted a friend for a ride on September 3 and said that he needed “help to clean up mess.” That friend declined to help.

Tessier is in police custody and will make his first court appearance Thursday.

Police say Tessier is currently their only suspect in Wallen’s death. Investigators did not say how Wallen was killed, and the investigation is ongoing.

Police: We were very interested in what he had to say at press conference; fam knew he was suspect @cbsbaltimore pic.twitter.com/HTKsMVsOpT — Mike Hellgren (@HellgrenWJZ) September 14, 2017

A vigil was scheduled for Wallen Wednesday night at Wilde Lake High School but was canceled following the announcement of her murder. Current and former students and members of the community had gathered in hopes of Wallen’s safe return.

Once word spread that she’d been found dead and that her boyfriend had been arrested and charged with her murder, those able to speak were basically left at a loss for words.

“It’s unreal,” former student Saquan Maxwell said. “It’s like one of them bad Lifetime movies that you just like ‘yeah I know what’s going to happen in the next five minutes of the movie,’ like it’s not real. Why? Like why? Like what motivated you, like why? Like how could you be so possessed with hate?”

“The community is devastated,” said Rick Wilson. “Our heart goes out to the Wallen family.”

“She influenced us to be better in life not just in school, in life,” former student Hamad Wasti said.

“While all of our hearts are broken they know that their dear Laura is secure in the arms of God and they are holding onto the faith,” family pastor Mark Hricko said.

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