Iran has apparently made arrests in last week's bomb assassination of a nuclear scientist there, but while it's said Israel was to blame for the attack, it hasn't said whether the people it's now questioning are actually from Israel or connected to it. In fact, details are pretty scarce overall about the news, except that an Iranian politician says the arrests happened. "We have discovered some clues, and some arrests have been made. Investigations are ongoing," parliament speaker Ali Larijani told Arabic-language broadcaster Al Aram. He didn't say who authorities arrested or where they were from, but he did keep up the anti-Israel rhetoric, if only generally: "We will not hesitate in punishing the Zionist regime [Israel] so that it realizes such actions have clear responses. There will definitely be a response, but our action will be of a non-terrorist nature," he said, according to Agence France-Presse via the New York Post. The U.S. has denied any involvement in the killing, while Israel has said nothing official about it, one way or the other.