Palestinian medical officials say six Palestinians have been killed and at least 26 others wounded in clashes with Israeli forces in the southern Gaza Strip.
They say two civilians, including a 40-year-old bystander and a Hamas militant's mother, are among the dead. Three Hamas fighters and an Islamic Jihad militant have also been killed.
The Israeli army says its forces began carrying out ground operations and air strikes targeting armed militants early Tuesday near the town of Khan Yunis.
The Israeli army says troops were conducting an operation to search and destroy tunnels along the frontier in an effort to prevent cross-border Palestinian rocket fire. Israel said its soldiers opened fire when they encountered Palestinian gunmen.
Israel says its forces have also detained about 100 people for questioning.
Some information for this report was provided by AP and AFP.