It may be proof even thieves have consciences.

Sure, they robbed a California non-profit group that helps sexual assault victims last Friday. But they ended up returning the stuff. And, judging by the kind note they left, they seemed to be really sorry about it.

"I got chills when I saw the note," San Bernardino Sexual Assault Services Executive Director Candy Stallings told ABCNews.com. "I was teary eyed, and I had so many mixed emotions."

"A police officer I was with at the time said they had never seen anything like this in the 20 years they were on the force," Stallings added. "We were shocked, completely shocked."

(Candy Stallings)

Stallings said she received a phone call from her alarm company at 10:30 p.m. Friday informing her that the motion detectors at the group's office building had detected movement and that the alarm had gone off.

"I headed down to the office and I was like, 'Oh, my goodness, this is going to be terrible,'" Stallings said. "We have never been broken into because we are very cautious and lock our doors all the time."

Stallings headed down to the center, where she saw a San Bernardino police helicopter flying overhead. Police and a canine unit were investigating the break-in.

Inside, she said, the building's telephone wires had been cut, its Internet connection was down and six computer towers, a laptop, speakers for the laptop, children's story books and 100 bags of small candy had been stolen.

The investigation wrapped up around 2 a.m., Stallings said, so she returned home.

But she heard again from police about two hours later.

"I got a call from San Bernardino Police directly, who said, 'Candy, can you please come back down? We have some suspicious activity,'" she said. "And I was thinking to myself, 'This is too much. We are not going to recover from this.'

"The officer who was monitoring the building after the robbery noticed a shopping cart in front of the door filled with what I initially thought were additional items," she added.

But it turned out someone had returned the stolen items along with a note inside the laptop apologizing for the theft, San Bernardino Police Department Sgt. Vicki Cervantes told ABCNews.com.

"When I looked inside the cart I thought, 'These are our items that they had taken before. This doesn't make any sense. Why would they bring it back?'" Stallings said. "And then, an officer found the note inside the laptop as he was taking fingerprints."

The note read: "We had no idea what we were taking. Here is your stuff back. We hope that you guys can continue to make a difference in people's lives. God Bless."

"I started thinking that even though I was upset with the damage they caused inside, because it was very costly, I just thought sometimes people make bad choices and it was compassion that brought those items back to us," she said. "I've been at this agency for 26 years and we have never ever had something that touched us like this."

The following day, authorities realized the burglars had entered the building through a small hole in the roof, Cervantes said.

"I couldn't visualize that our place had been burglarized by just a shopping cart, because it felt like it was much more sophisticated and no windows were broken," Stallings said.

No suspects have been apprehended and the investigation is still ongoing, Cervantes said, adding that, although the items were returned, the thieves will be held accountable for their crime.

"They still committed the crime and it is still considered a burglary," Cervantes said. "It doesn't negate that. There may be a lessened sentence, but the crime and charges are still the same."

The San Bernardino Sexual Assault Services building is not clearly marked because the center wants people who enter to feel comfortable walking in without feeling like they are being judged, Stallings said.

"Our building does not have our full name on it, so it is likely the thieves wouldn't know what we do here," Stallings said. "But when they found out, they obviously changed their minds and decided to return the stolen items."

Stallings said she appreciated that the items were returned and wondered who the mystery thieves were and what prompted them to return the items.

"Most of the time, individuals don't pay attention to services like sexual assault unless you've been touched by the crime, or received service yourself or have been in contact with someone who has been victimized," she said. "These individuals felt compelled to give back for some reason. And, of course, I don't know officially, but that's my gut feeling that they were close to the cause. It was a terrible night, but it ended in disbelief. We are thankful everything has been returned."