BEIRUT (AP) — The Lebanese military said a group of Israeli soldiers crossed the border into Lebanon and were wounded in an unspecified explosion early Wednesday — a rare incident along the heavily guarded and volatile frontier.

The Israeli side appeared to dispute the location of the incident, saying four soldiers were wounded while carrying out routine activities along the border with Lebanon.

Defense Minister Moshe Yaalon said a blast wounded four soldiers, some lightly, others moderately, "in operational activity along the Lebanon border."

He said the troops were carrying out routine activities "aimed at providing quiet to the residents of the north in particular and the residents of Israel in general."

"During the operational activity, the force came upon an explosive," he said, adding that the military was investigating whether the blast was caused by an old or new explosive.

"But this activity was done and will be done again responsibly and in consideration for the security of the people of Israel," Yaalon added.