A suspect was in custody after a shooting that killed two people Friday morning at a senior living facility in Capitol Heights, Maryland.

A third person was also wounded, reports said.

Gunfire erupted shortly after 9 a.m. at 505 Suffolk Ave., outside Washington D.C. A website for National Church Residences identifies the address as that of Gateway Village, which offers affordable rental apartments for seniors age 62 and over.

It was unclear what exactly prompted the shooting.

Later in the day, officials confirmed the two deceased victims were female employees at the facility, according to NBC4 in Washington, which cited the Prince George’s County Police Department. Their names were not immediately released. One was found in a hallway and the other in an office, NBC4 reported.

The gunman was believed to be a resident of the complex, according to 7News DC, citing witnesses at the scene.

LiveNOW Fox reported that the suspect may have opened fire on the employees in retaliation for alleged mistreatment of residents who lived there.

About 90 residents of the facility were evacuated to a staging area a few blocks away as police secured the scene, reports said.

Prince George’s County Police confirmed the arrest of a suspect but have not yet released his name. Officers were searching the facility in case there were more victims.

Residents in the neighborhood were advised to shelter in place, and a nearby elementary school was placed on lockdown.

The suspect reportedly barricaded himself for a short time on the top floor of the building before authorities moved in, according to DC Metro News. The suspect was taken into custody at 10:25 a.m., a little more than an hour after the shooting started.

This is a developing story. Please stay with AJC.com for the latest updates.