A supposed makeshift grenade was thrown at an Israeli bus transporting students to schools on Friday morning in the northern West Bank near the village of Yaabud, west of Jenin.
No injuries or damage were reported.
Security forces were sweeping the area.
The IDF could not confirm the identity of the perpetrator.
"I hope now there will be an aggressive decision to bring attention to the area to prevent further attacks," Army Radio quoted Shomron Regional Council head Gershon Mesika as saying.
"This road was recently opened for vehicles traveling between Jenin and Tulkarm. Once, the road was closed, now it is open, and constitutes an existential threat to travelers," he added.
On Tuesday, Defense Minister Moshe Ya'alon warned that an "infectious wave of terror attacks"
had been seen in the West Bank over the past month, but said he did not see signs of a third intifada.
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