He shook his head even as Cormac started casting, knowing it was useless anyway. He suspected it was Rabastan, was pretty much completely sure in fact, but they'd never be able to arrest him. He couldn't imagine Rodolphus letting Bellatrix out of his sight for the moment, not after the Lighting Ceremony or when he knew Aurors would be crawling all over the place.
"My hunch is that it's one of the Lestranges and I'd suspect Rabastan and another, possibly his girlfriend from the descriptions we did get," he said finally. "If we want a magical signature, we'd be best off going upstairs to the rape victim. His prints will be all over her."
He let Cormac deal with the foreign Aurors, him and Cass cleaning up the crime scene before they all moved on to the lobby. There were a few bodies here, another cut throat and those with the entrails outside their bodies. "No prints, cut throat..." He paused, casting a spell. "Something dark's been used, possibly an Unforgivable... Likely the Cruciatus seeing as I don't know what could have been gained from the Imperius and the Killing Curse wasn't the cause of death."
He looked over at Cass and stood back so Cormac could start taking the photographs. "Anything else you've noticed?"