The investigation into the missing Fort Hood soldier Vanessa Guillen took a grim turn on Wednesday after a suspect shot himself in front of the police in Killen, Texas. As officers approached the man, an active-duty soldier, he pulled out a gun and committed suicide.

The Killeen Police Department and the United States Army Criminal Investigation Command confirmed in a statement that one of the suspects in Guillen's disappearance, a man identified as Aaron David Robinson, died by suicide as police closed in on him.

David Robinson
David Robinson Twitter

Early on Wednesday, US Marshals, Killeen police and the Lone Star Fugitive Task Force tried to locate the suspect but had learned that he had left the base and was in the city of Killeen. He was later found walking down a street shortly after 1 a.m. when the police confronted him.

"As officers attempted to make contact with the suspect, the suspect displayed a weapon and discharged it toward himself. The suspect succumbed from a self-inflicted gunshot wound," the Killeen Police Department said in a news release.

According to army officials, authorities also arrested a second suspect, a woman named Cecily Anne Aguilar who officials say is the estranged wife of a former Fort Hood soldier. She is currently in custody in the Bell County Jail awaiting unspecified charges.

Cecily Aguilar
Cecily Aguilar Twitter

Human Remains Found on Tuesday

On Tuesday, investigators discovered the partial human remains of a body in a shallow grave near the Leon River in rural Bell County. The remains were found encased in concrete. The fresh concrete was poured directly onto the body and the grave was covered with rocks. Rain that fell after Guillen vanished likely helped settle the disturbed earth and hid the grave.

Vanessa Guillen
Vanessa Guillen Twitter

While authorities have not yet confirmed it and the medical examiner is yet to formally identify the corpse, Guillen's family said "everything points to it being her" in an emotional press conference on Wednesday.

Robinson Watched Guillen Taking a Shower

Guillen's family has been demanding answers ever since the Private First Class disappeared on April 22, following complaints that she was being sexually harassed by one of her sergeants at Fort Hood.

According to the attorney representing the soldier's family, there was at least one incident involving a superior officer walking in on Guillen while she was showering and he stayed and watched. Robinson was identified as the sergeant who walked in on Guillen, according to legal documents leaked on social media.

David Robinson
The document leaked on social media. Twitter

Guillen was last seen in the parking lot of her barracks before going missing and her car keys, room key, identification card and wallet were found in an armory room where she was working that day. Coincidentally, Robinson also happens to be an arms room NCO.

While we do not know how Aguilar, the other suspect arrested in the case, is connected to the case, she was allegedly dating Robinson despite being married to another soldier and may have been an accessory to the crime.