A United Nations observer was seriously wounded Sunday in the crossfire during fighting between Hizbullah and Israeli troops in south Lebanon, and flown to an Israeli hospital for treatment, officials said. The observer, identified as Italian army Capt. Roberto Punzo, was wounded by "fragments," the office of the Italian chiefs of staff said, adding that the source of the fragments was not immediately clear. Earlier a UN official said he had been wounded by a bullet, apparently fired by Hizbullah. Punzo was evacuated by an Israeli military helicopter to Rambam Hospital in Haifa and admitted for emergency care, said hospital spokesman David Ratner. Ratner said he was undergoing surgery for a stomach wound and was in serious but stable condition. Punzo is the second member of the UN monitoring team injured in 12 days of fighting. Several UN positions on the border have taken hits from Israeli shells, and Israel said earlier this week that a UN post on its side was hit by a Hizbullah missile - though the observer team said it was a stray Israeli shell.