Authorities are investigating two break-ins this week at a Northeast Washington mosque in which holy books were upended and a large picture of an Islamic holy site was stolen, according to D.C. police and the center’s religious leader.

A police spokesman, Lt. Sean Conboy, said neither incident at the Ivy City Masjid and Islamic Education Center, on Gallaudet Street, is being investigated as a hate crime.

The FBI is monitoring the situation but has not opened a formal investigation.

“We’ve been in contact with representatives of the mosque,” said Andrew Ames, a spokesman for the FBI’s Washington field office.

The first break-in, on Monday, has been categorized as a destruction of property; the second, Wednesday night or Thursday morning, is listed as a second-degree burglary. No arrests have been made.

Mohammad Mobaidin, the center’s director, said that the mosque has been in the Ivy City neighborhood, just off New York Avenue, for 15 years and that it is often left open for people to go in and pray.

Between 6:30 and 8:30 p.m. Monday, Mobaidin said, shelves with holy books on them were broken. He also said a chair was apparently used to break plate glass in the center.

Mobaidin said he didn’t think it was a case of hate crime, but after the second incident — which occurred between 7 p.m. Wednesday and 11 a.m. Thursday — he is more concerned. He said that the sound system had been flipped upside down and that a large picture of the Kaaba — a shrine at the Grand Mosque in Mecca, Saudi Arabia, Islam’s holiest site — had been stolen.

Mobaidin said he has been part of the neighborhood for 20 years, owning a grocery store and taxi company before running the mosque. “I have never had any problem whatsoever because I’m Muslim or a foreigner,” he said.

The mosque, Mobaidin said, has had programs to feed children and help seniors.

“I doubt it very seriously that someone in the community would do something this vicious to us,” he said, estimating the damage at $4,000. “It is just mind-blowing someone would damage a sacred place, where people come in peace to worship. . . . It gives you a really bad feeling about other people doing things like that.”

But he said the situation is “strengthening my resolve.”

He added: “Our neighbors are with us. . . . We are not backing out. We are here to stay. We are law-obeying citizens. Our main goal is peace. And our main goal is to worship God.”