Pregnant Teacher's Boyfriend Charged in Her Killing Sent Texts Pretending to Be Her: Arrest Warrant

Tyler Tessier, 32, also allegedly admitted to being engaged to another woman.

The boyfriend of a pregnant Maryland teacher found dead in a shallow grave was engaged to another woman and sent text messages as the slain mother-to-be claiming the unborn baby wasn't his, court documents said.

The day Jennifer Kadi reported her sister Laura Wallen missing, she told police she received texts from her 31-year-old expectant sister’s phone that shared a very serious message.

“I am like 95 percent sure Tyler is not the father,” the text from Wallen’s phone read, according to an arrest warrant released.

Tyler Tessier, 32, was Wallen’s on- and off-again boyfriend of seven years, and the pair was expecting their first child together.

Tessier had asked Wallen’s father for permission to marry his daughter and by all accounts, had been very supportive of the pregnancy. And Wallen was very excited to become a mom.

Then on Sept. 4, Kadi received the texts.

One text from Wallen’s phone noted she was “going to try and get a hold of” a man she had previously dated.

“Tyler is never going to forgive me,” another message said. “If he tries to call you, please tell him he’s a great guy because I know I really hurt his feelings.”

Read: Boyfriend Arrested for Alleged Murder of Pregnant Teacher Found in Shallow Grave: Cops

But the texts didn’t sound like Wallen and whoever was sending the texts had spelled the name of the other man wrong, Kadi told police.

Besides, her sister continued, she wouldn’t share news like this through a text.

Investigators determined that Wallen and the other man hadn’t seen each other in two years.

On Sept. 5, Wallen failed to show up for the first day at Wilde Lake High School in Columbia, where she worked as a teacher.

Wallen had been excited for the new school year. She was busy getting her classroom ready and preparing for an upcoming fundraiser. It was extremely unusual for her to not show up for work without notifying anyone.

Tessier allegedly gave conflicting accounts of his interactions with Wallen to police during four separate interviews from Sept. 5-11, officials said.

He allegedly admitted he was engaged to another woman, unbeknownst to Wallen.

Investigators found Wallen texted the other woman on Aug. 28, writing: “It’s important that some things are cleared up and I would imagine that if you were in my position, you’d want some answers as well. By no means is this an attempt at confrontation, just looking for an explanation... woman to woman.”

Police said Tessier later admitted to driving Wallen’s car to the location in which it was recovered, as well as disposing of her phone and driver’s license that were found by a maintenance worker on Sept. 4.

Read: Man Accused of Killing Pregnant Girlfriend Faked Plea for Her Safe Return: Cops

He claimed he did these things because Wallen told him a previous boyfriend was the father of her baby and that she needed time to make a decision about what to do next, cops said.

“Tessier stated that he had disposed of Wallen’s license plate, iPhone and driver’s license in order to ‘buy her time’ to figure out what she was going to do about [redacted] being the baby’s father,” the warrant said.

He also allegedly admitted to sending Kadi text messages from Wallen’s phone.

Wallen’s remains were found in a shallow grave in Damascus. A medical examiner will determine the cause of death.

While Wallen was missing, Tessier was seen several times at the site where her body was later found, authorities said.

Detectives obtained a search warrant for the area, and police with cadaver dogs found Wallen’s body.

Tessier was arrested Wednesday and charged with first-degree murder.

Watch: 2 Charged in Connection With Pregnant Woman's Death After Being Found With Baby