A 7-year-old girl critically wounded Friday in Southeast Washington may have been accidentally shot when her 10-year-old brother tried to take a gun from her that she had found under their mother's bed after the siblings were left alone in the apartment, D.C. police said yesterday.

"The gun was in her hand, and he was trying to get it away from her," said a high-ranking police official who spoke on the condition of anonymity. "The brother attempted to do the right thing, but he didn't know what he was doing, trying to take a weapon from someone."

When officers arrived at the home in the 3300 block of 22nd Street SE about 4:30 p.m. Friday, they found the bleeding girl lying on her back on the floor, according to police.

"The girl was in a conscious but unresponsive state," the official said, adding that it appeared as if the bullet pierced her hand before tearing through her chest.

The brother was waiting in the apartment when the officers showed up, police said, and it was unclear who called 911 after the shooting.

Shannon Dooman, a spokeswoman for Children's Hospital, where the girl underwent surgery, said yesterday afternoon that the child remained in critical condition. Dooman gave no other details about the girl's status.

The police official said it is believed that the children's mother was at work at the time of the shooting.

Police spokesman Joe Gentile said the department's special victims unit served a warrant at the apartment and found two handguns that are being analyzed. A police source said one of the firearms was a high-powered automatic handgun, which is believed to be the weapon that discharged during the Friday shooting.

Investigators were searching the apartment and surrounding area for fragments of the bullet that passed through the girl's body, authorities said.

The District's Child and Family Services Agency is planning an investigation to determine whether the children should remain in their mother's custody, according to authorities, who said the father's whereabouts were unknown.

No criminal charges have been filed, law enforcement authorities said.