INDIANAPOLIS -- Blood that was found at a Benton County woman's house is that of her grandson who has been missing since August, Indiana State Police said Tuesday.

Police announced the finding after receiving results of a test. Regarding the blood, investigators say only that it confirms Nicolas Zavala -- who was 12 when he was reported missing Aug. 13 -- was at the home at some point, according to state police Sgt. Shana Kennedy.

The boy had been living in the Oxford home with his grandmother, Margaret Williams, for a few months at the time of his disappearance, police said.

Police found the blood during an October search of the home. Police said they had no further information on the investigation Tuesday.

Williams reported Nicolas missing Aug. 13, saying he did not return from a camping trip for which he had left a week earlier.

She told police she dropped him off Aug. 4 at Oxford's library, where he was to meet with two friends and their uncle to leave for the trip.

Williams told investigators she didn't know the names, addresses, or phone numbers of the three people. Investigators also have not been able to identify them, having checked with local schools.

State police say they are waiting for results of additional tests on evidence taken from Williams' home. Details about the evidence were not released.

Williams was charged in October with neglect. Prosecutors contend Williams should have known the people she claims took Nicolas on the camping trip.

Williams, who is free on bail, is scheduled to go on trial in late April.

Anyone with information on the case can call state police at (800) 382-7537 or (765) 463-1515.