U.N. troops respond to a large explosion in the southern Lebanese town of Tair Harfa, three miles from the border with Israel.

There were no casualties in the blast.

A Lebanese security source said it was caused by an unexploded rocket that had been fired into Lebanon during the 2006 war with Israel.

But a spokesman for the U.N. peacekeeping force in Lebanon said soldiers in the area were still trying to determine the cause.

The explosion did kill several farm animals in a field, according to local residents.

The U.N. has deployed about 12,000 troops and naval personnel in Lebanon since the 2006 war.