Russian fighter jets today fired rockets at the presidential palace in Grozny three times, despite Russian President Boris Yeltsin's public order Wednesday to halt furtherair raids on Chechnya's ruined capital. At least one bomb hit the tall concrete building squarely, setting off a fire on the upper floors, but claiming no casualties as Chechen officials kept to the basement and first floor. (Chechnya's president, Dzhokhar Dudayev, reportedly is concealed in a bunker elsewhere.) TIME Moscow bureau chief John Kohan says the action by the Russian military -- who are no nearer to containing the crisis -- suggests Yeltsin's authority is in jeopardy. "There are serious questions that have to be raised when the commander-in-chief gives an order and it's disobeyed," Kohan says. "One has the sense in general that this is a war in which they've broken every single rule that applies to modern warfare." Secretary of State Warren Christopher said today that he supported Russia's right to suppress armed insurrection but worried that Yeltsin's military assault has escalated out of his control; in Germany, Chancellor Helmut Kohl called the Russian leader to press for an end to the violence.