UNITED NATIONS: The United Nations slammed as "unacceptable" an overnight attack against peacekeepers in southern Lebanon, spokesman Stephane Dujarric said Wednesday.

The peacekeepers -- members of the United Nations Interim Force in Lebanon (UNIFIL) -- were attacked late Tuesday night by "unknown perpetrators," he said.

"Their UN vehicles were vandalized and official items were stolen," Dujarric said, without specifying the nature of the damage or the state of the victims.

He noted that the peacekeepers were not on private property or taking photos, "contrary to some subsequent media disinformation."

Instead, they were en route to meet Lebanese Armed Forces members for a "routine patrol," he said.

"The denial of UNIFIL's freedom of movement and any aggression against those serving the cause of peace is unacceptable," said Dujarric, before calling on the Lebanese government to "investigate quickly and thoroughly, and prosecute all those responsible for these crimes."

UNIFIL -- comprised of about 13,000 UN peacekeepers -- has operated in southern Lebanon since 1978, and is responsible for monitoring the ceasefire along the border with Israel.