The FBI is offering a reward of $28,000 for information leading to an arrest after two people were shot to death and 28 more injured at a South Baltimore block party Sunday, the agency said in a statement Monday afternoon.

Police are searching for suspects in the shooting, which took place just after 12:30 a.m. Sunday in the Brooklyn Homes area, according to Richard Worley, Baltimore's acting police commissioner. Worley said it wasn't clear if the shooting was targeted or random.

Baltimore police are investigating why authorities were not posted at the "Brooklyn Day" party, which is held annually and normally has a police presence, officials said at a Sunday afternoon news conference streamed by CBS News Baltimore.

"That's what we're trying to investigate," Worley said during the conference. "This was an unpermitted event, so our job now is to figure out when we figured out that this was occurring and what our officers did. If we made mistakes we'll fix them and move forward so that this does not happen ever again."... Read More: Pikesville Patch