“The United States was not involved whatsoever in these events,” said Marie Harf, a State Department spokeswoman.

But the targets indicated the intent of the strikes. Although the month-old conflict in Tripoli is largely a contest for power between rival coalitions of cities and tribes, one side is considered to be allied with the forces of political Islam, while the other portrays itself as fighting an Islamist takeover. The strikes on Monday all hit the Islamist side.

Representatives of a renegade former general, Khalifa Hifter sought at times on Monday to claim responsibility; General Hifter is fighting to purge eastern Libya of its Islamist fighters. But the accounts were inconsistent, and General Hifter’s forces — mainly leftovers from the Libyan military — are not believed to have the capacity for the strikes, either.