A woman has been arrested in connection with the disappearance of a Fort Hood soldier who has been missing since April, the Army said on Wednesday. A second suspect, identified only as a soldier, took his own life in Killeen, Texas, on Tuesday, the Army said.

The missing soldier, Pfc. Vanessa Guillen, 20, was last seen at Fort Hood on April 22, according to the Army Criminal Investigation Command.

The name of the deceased suspect, whom the Army described as a junior soldier, was not released on Wednesday pending the notification of his family. Chief Charles F. Kimble of the Killeen Police Department said at a news conference on Wednesday that the soldier shot himself as officers approached him on Tuesday.

The Army described the woman who was arrested as the estranged wife of a former Fort Hood soldier. She was in custody in the Bell County jail awaiting the filing of charges. Her name was not immediately released.

The arrest and the suicide were announced as the Texas Rangers, the Army CID and other agencies continued to process the scene near the Leon River in Bell County, Texas, where partial human remains were found on Tuesday. The Armed Forces Medical Examiner Service is assisting the Southwestern Institute of Forensic Sciences in Dallas with dental X-rays and DNA analysis to identify the remains.

Guillen was last seen wearing a black T-shirt and purple fitness-type pants in the parking lot of the Regimental Engineer Squadron Headquarters at Fort Hood between 11:30 a.m. and 12:30 p.m. on April 22.

Her car keys, barracks room key, identification and wallet were found in the armory room where she had been at work repairing small arms and artillery.

Since she disappeared, more than 500 soldiers have searched for Guillen in buildings, barracks, fields, training areas, lakes and trails at Fort Hood, according to base officials.

“We have made significant progress in this tragic situation and are doing everything possible to get to the truth and bring answers to the family of Pfc. Vanessa Guillen,” the Army CID said in a statement on Wednesday.

As they awaited the identification of the remains, Guillen’s family members gathered with their lawyer, Natalie Khawam, in Washington on Wednesday to demand a congressional investigation into her disappearance.

“As you know, it is not confirmed yet whether it is my sister or not,” Mayra Guillen, one of Guillen’s sisters, said at a news conference in front of the U.S. Navy Memorial. “At this point, everything points to it.”