The body of a pregnant high school teacher in Maryland has been found and now her boyfriend, and the baby’s father, is charged with her murder.

Lauren Wallen had been missing for nine days and missed the first day of the new school year on Sept. 5. Her boyfriend, Tyler Tessier, had pleaded for her return days before she was found dead in a shallow grave, WJLA reported.

“If somebody has her, please understand that you’ve taken away a huge person in so many people’s life,”Tessier said Monday. “I don’t know where she is. I don’t know. I pray that she’s safe and that she comes back. That’s all I care about.”

But police had a feeling that Tessier’s story during a news conference wasn’t the truth.

“The decision to allow him to participate in that news conference was a calculated decision made by the detectives in this case for the express purpose of hearing what he had to say. It was done with the approval and knowledge of the victim’s family,” Montgomery County Police Chief Tom Manger said.

Wallen's parents had offered a $25,000 reward for information leading to Wallen's location, WJLA reported.

Tessier had been the last one to see Wallen before she disappeared. They were together at a grocery store near her home on Saturday, Sept. 2.

Police said she then texted a friend that Tessier had taken her to a field near Damascus, Maryland and she wasn’t sure why he did.

Wallen's sister said she also received what she described as a "troubling" text message from Wallen's phone on Sept. 4. But police said it wasn't Wallen who sent the text that claimed the baby wasn't her boyfriend's child. Instead, police said, Tessier sent the text himself, WRC reported.

Police said that Tessier also took Wallen’s SUV and parked it not far from the high school where she worked. Police said that he admitted to getting rid of the front license plate, her driver’s license and her iPhone.

The SUV was found at an apartment complex on Sept. 7, WRC reported.

Wallen’s body was found in a shallow grave in the woods Wednesday.

Police are not sure of Tessier's motive, but he has been charged with murder. An autopsy will determine Wallen's cause of death, WRC reported.