WASHINGTON -- Israel warned U.S. Defense Secretary Lloyd Austin in a call Tuesday that a military operation was going to take place in Lebanon but gave no details, U.S. officials said Thursday. The same day of the call, in an attack widely blamed on Israel, thousands of pagers belonging to Hezbollah militants exploded.

U.S. officials say Israel warned U.S. Defense Secretary Lloyd Austin in a call Tuesday that a military operation was going to take place in Lebanon

By Laila Bassam and Maya Gebeily BEIRUT/JERUSALEM (Reuters) -Israeli warplanes carried out late on Thursday their most intense strikes on southern Lebanon in nearly a year of war, heightening the conflict between Israel and Lebanese armed group Hezbollah amid calls for restraint.

Israel launched a series of strikes on Hezbollah targets Thursday as the war against the Lebanon-based group widened in the wake of two consecutive days of deadly explosions triggered in wireless devices.

Israel bombed southern Lebanon on Thursday and said it had thwarted an Iran-backed assassination plot, a day after explosions of Hezbollah radios followed blasts in booby trapped pagers, setting the foes hurtling towards war.

Israeli Defense Minister Yoav Gallant ushered in what he called a “new phase” in the war with regional Islamist groups and said troops would be diverted to the Lebanese border, an indication that long-held fears of a wider conflict may soon be realized.