An IDF unit sent to Jenin overnight to arrest seven security suspects came under fire from Palestinian gunmen.
Attackers also threw explosives at soldiers.
The IDF is checking the possibility that one of the gunmen was hit by army fire. There were no injuries among soldiers.
During clashes that ensued in the West Bank city, one rock-thrower was arrested. In raids on the homes of security suspects, soldiers uncovered a firearm, improvised explosives, and ammunition, an army spokeswoman added.
The wanted men were taken in for questioning.
An additional five Palestinian suspects were arrested during raids in other West Bank locations, including in Zawata, northwest of Nablus, where a suspect was found to be in possession of homemade weapons.