William Barker, 42, was charged with unlawful entry. (Arlington County Police Department)

For three years, nobody at St. Ann Roman Catholic Church in Arlington knew about the homeless man living in the attic. Sure, police said, some members wondered about missing food from time to time.

But nobody — not the pastor, not the members and not the 190 children who attend St. Ann School — knew that William Barker, 42, was upstairs the whole time, squatting, according to Arlington County police. It wasn’t until Monday, when an air conditioning repairman stopped by and heard loud noises from above the kitchen, that police were summoned and discovered Barker in the attic. Up there, authorities found a cooler with food and water, clothes hanging on a rafter and a guitar.

“I had no clue about this, and I am a reasonably active church person,” said St. Ann’s member and volunteer Mary Green. “The situation shows the dreadful plight of homeless people. On the one hand, we don’t want strange people around school. But on other hand, this guy needed help.”

Police said Barker acknowledged that he had been living in the attic for three years. Barker was charged with unlawful entry and is being held without bond. His next hearing is Nov. 19.

The Rev. Ramel O. Portula, the church’s pastor, and Elise Italiano, the director of communications for the Catholic Diocese of Arlington, declined to comment.

Green, the church volunteer, said Portula e-mailed St. Ann members this week about the incident. “He was talking about protecting the children,” Green said.

Dustin Sternbeck, an Arlington police spokesman, said Barker has been arrested five times in the county, twice on accusations of burglarizing a church in 2013 and 2008. He was also charged with indecent exposure in 2007.

Maj. Susie Doyel, director of administration for the Arlington County Sheriff’s Office, said Barker declined an interview request from The Washington Post.

After his arrest Monday, Barker told officers that he would wait for a quiet moment at St. Ann, a red-brick building with a short white steeple, and then use a ladder to climb up to his makeshift bed, police said.

Sternbeck said Barker’s hidden room was discovered at about 5 p.m. Monday, after the air conditioning repairman reported the noises. A church official was called and authorities were notified, he said.

Officers used a ladder to climb up to the attic, where they found Barker, Sternbeck said.

“He had hoped the police would leave without coming up there,” Sternbeck said.

According to Sternbeck, Barker told authorities that he began attending services at St. Ann after having a meal there. After services, staff members would disperse, and he would use the ladder — which he would pull up into the attic with him — and move a ceiling tile back in place to disguise the hideaway.

Barker was charged with burglary in connection with a break-in at another church, Sternbeck said. During that incident, police caught Barker on camera at the Cathedral of St. Thomas More, where authorities said he smashed the window and stole a number of items, including food and a gift card.

Sternbeck said Barker is being held and awaiting a mental health evaluation.